Removed trailing spaces in the most relevant files

Command used for the job:
egrep -rl ' $' --include *.c --include *.h --include  *.s --include  *.inc --include  *.txt *  | xargs sed -i 's/\s\+$//g'

Credits to Grant Murphy from Stack Overflow.

src/main_menu.c

@@ -40,17 +40,17 @@
 /*
  * Main menu state machine
  * -----------------------
- * 
+ *
  * Entry point: CB2_InitMainMenu
- * 
+ *
  * Note: States advance sequentially unless otherwise stated.
- * 
+ *
  * CB2_InitMainMenu / CB2_ReinitMainMenu
  *  - Both of these states call InitMainMenu, which does all the work.
  *  - In the Reinit case, the init code will check if the user came from
  *    the options screen. If they did, then the options menu item is
  *    pre-selected.
- * 
+ *
  * Task_MainMenuCheckSaveFile
  *  - Determines how many menu options to show based on whether
  *    the save file is Ok, empty, corrupted, etc.
@@ -59,33 +59,33 @@
  *  - If there were no errors, advance to Task_MainMenuCheckBattery.
  *  - Note that the check to enable Mystery Events would normally happen
  *    here, but this version of Emerald has them disabled.
- * 
+ *
  * Task_WaitForSaveFileErrorWindow
  *  - Wait for the text to finish printing and then for the A button
  *    to be pressed.
- * 
+ *
  * Task_MainMenuCheckBattery
  *  - If the battery is OK, advance to Task_DisplayMainMenu.
  *  - If the battery is dry, advance to Task_WaitForBatteryDryErrorWindow.
- * 
+ *
  * Task_WaitForBatteryDryErrorWindow
  *  - Wait for the text to finish printing and then for the A button
  *    to be pressed.
- * 
+ *
  * Task_DisplayMainWindow
  *  - Display the buttons to the user. If the menu is in HAS_MYSTERY_EVENTS
  *    mode, there are too many buttons for one screen and a scrollbar is added,
  *    and the scrollbar task is spawned (Task_ScrollIndicatorArrowPairOnMainMenu).
- * 
+ *
  * Task_HighlightSelectedMainMenuItem
  *  - Update the UI to match the currently selected item.
- * 
+ *
  * Task_HandleMainMenuInput
  *  - If A is pressed, advance to Task_HandleMainMenuAPressed.
  *  - If B is pressed, return to the title screen via CB2_InitTitleScreen.
  *  - If Up or Down is pressed, handle scrolling if there is a scroll bar, change
  *    the selection, then go back to Task_HighlightSelectedMainMenuItem.
- * 
+ *
  * Task_HandleMainMenuAPressed
  *  - If the user selected New Game, advance to Task_NewGameBirchSpeech_Init.
  *  - If the user selected Continue, advance to CB2_ContinueSavedGame.
@@ -95,15 +95,15 @@
  *    Task_DisplayMainMenuInvalidActionError.
  *  - Code to start a Mystery Event is present here, but is unreachable in this
  *    version.
- *    
+ *
  * Task_HandleMainMenuBPressed
  *  - Clean up the main menu and go back to CB2_InitTitleScreen.
- * 
+ *
  * Task_DisplayMainMenuInvalidActionError
  *  - Print one of three different error messages, wait for the text to stop
  *    printing, and then wait for A or B to be pressed.
  * - Then advance to Task_HandleMainMenuBPressed.
- * 
+ *
  * Task_NewGameBirchSpeechInit
  *  - Load the sprites for the intro speech, start playing music
  * Task_NewGameBirchSpeech_WaitToShowBirch
@@ -126,11 +126,11 @@
  *  - Animates by advancing to Task_NewGameBirchSpeech_SlideOutOldGenderSprite
  *    whenever the player's selection changes.
  *  - Advances to Task_NewGameBirchSpeech_WhatsYourName when done.
- * 
+ *
  * Task_NewGameBirchSpeech_SlideOutOldGenderSprite
  * Task_NewGameBirchSpeech_SlideInNewGenderSprite
  *  - Returns back to Task_NewGameBirchSpeech_ChooseGender.
- * 
+ *
  * Task_NewGameBirchSpeech_WhatsYourName
  * Task_NewGameBirchSpeech_WaitForWhatsYourNameToPrint
  * Task_NewGameBirchSpeech_WaitPressBeforeNameChoice
@@ -144,7 +144,7 @@
  * Task_NewGameBirchSpeech_ProcessNameYesNoMenu
  *  - If confirmed, advance to Task_NewGameBirchSpeech_SlidePlatformAway2.
  *  - Otherwise, return to Task_NewGameBirchSpeech_BoyOrGirl.
- * 
+ *
  * Task_NewGameBirchSpeech_SlidePlatformAway2
  * Task_NewGameBirchSpeech_ReshowBirchLotad
  * Task_NewGameBirchSpeech_WaitForSpriteFadeInAndTextPrinter
@@ -154,7 +154,7 @@
  * Task_NewGameBirchSpeech_FadePlayerToWhite
  * Task_NewGameBirchSpeech_Cleanup
  *  - Advances to CB2_NewGame.
- * 
+ *
  * Task_NewGameBirchSpeechSub_InitPokeball
  *  - Advances to Task_NewGameBirchSpeechSub_WaitForLotad
  * Task_NewGameBirchSpeechSub_WaitForLotad