Add a missing "=" in dumpsys input_method

My previous CL [1] lacked "=" when dumping

  NavigationBarController#mShouldShowImeSwitcherWhenImeIsShown

into dumpsys.  This CL fixes that typo.

 [1]: I5de9ac0dc8670842edf66306bb4c281c77cea376
      75b935a1

Bug: 215551357
Test: adb shell dumpsys input_method | grep NavigationBarController
Change-Id: Ifa2f5d2abcbe982b0afa5a6dad1573a86123485e