gallery: change typo '&&' to '||'

Assertion to ckeck array boundary should
be '&&' instead of '||'. It caused an
Exception that '-1' wasn't detected.

Change-Id: I991ad8efed87a0837d262fe7419c7f007c173b56
Signed-off-by: Leavitt Zhang <leavittz@nvidia.com>
TRDS: Darker Gallery

Change-Id: I632b252280118f61f356f4a6dae1039e02b82241