staging: rts5208: fix gcc-8 logic error warning

staging: rts5208: fix gcc-8 logic error warning

As gcc-8 points out, the bit mask check makes no sense here:

drivers/staging/rts5208/sd.c: In function 'ext_sd_send_cmd_get_rsp':
drivers/staging/rts5208/sd.c:4130:25: error: bitwise comparison always evaluates to true [-Werror=tautological-compare]

However, the code is even more bogus, as we have already
checked for the SD_RSP_TYPE_R0 case earlier in the function
and returned success. As seen in the mmc/sd driver core,
SD_RSP_TYPE_R0 means "no response" anyway, so checking for
a particular response would not help either.

This just removes the nonsensical code to get rid of the
warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>