staging: rts5208: Added value check

Added value check.
Return value of a function 'ms_set_rw_reg_addr'
called at ms.c:1770 is not checked,
but it is usually checked for this function

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Denis Arefev <arefev@swemel.ru>
Link: https://lore.kernel.org/r/20221118111523.123463-1-arefev@swemel.ru


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>