[SERIAL]: Avoid 'statement with no effect' warnings.
[SERIAL]: Avoid 'statement with no effect' warnings.

When SUPPORT_SYSRQ is false, gcc can emit warnings for
the uart_handle_sysrq_char() that results.  Using an
empty inline returning zero kills the warning.

Signed-off-by: David S. Miller <fe08d3c717adf2ae63592e4c9aec6e3e404d8e3e@davemloft.net>

KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs