media: verisilicon: Simplify error handling in tile_buffer_reallocate()

Rework allocation errors cases handling to simply it
by removing useless tests.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
Reported-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>