Add owner for include/android/keycodes.h

Because of the existence of extra spaces, the owner of keycodes.h is
not configured as expected. We should delete this extra spaces.

Bug: none
Test: After merging, check whether the owner of keycodes.h includes
all users under INPUT_OWNER

Change-Id: I634c49f53a4633bdee3cdefbf0debae4dff90a47

include/android/OWNERS

-per-file input.h, keycodes.h = file:platform/frameworks/base:/INPUT_OWNERS
+per-file input.h,keycodes.h = file:platform/frameworks/base:/INPUT_OWNERS