Staging: android: lowmemorykiller: cleanup android low memory killer

Clean up the code in lowmem_shrink() for the Android low memory killer so
that it follows the kernel coding style.

It's unnecessary to check for p->oomkilladj >= min_adj if the selected
task's oomkilladj score is stored since get_mm_rss() will always be
greater than zero.

Cc: San Mehat <san@android.com>
Cc: Arve Hjønnevåg <arve@android.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>