staging: rtl8723bs: remove some variables in hal_btcoex.c

staging: rtl8723bs: remove some variables in hal_btcoex.c

Fix the following gcc warning:

drivers/staging/rtl8723bs/hal/hal_btcoex.c:45:26: warning: ‘ioStaString’
defined but not used [-Wunused-const-variable=]
 static const char *const ioStaString[] = {
                          ^~~~~~~~~~~
drivers/staging/rtl8723bs/hal/hal_btcoex.c:38:26: warning:
‘h2cStaString’ defined but not used [-Wunused-const-variable=]
 static const char *const h2cStaString[] = {
                          ^~~~~~~~~~~~
drivers/staging/rtl8723bs/hal/hal_btcoex.c:33:26: warning:
‘BtLinkRoleString’ defined but not used [-Wunused-const-variable=]
 static const char *const BtLinkRoleString[] = {
                          ^~~~~~~~~~~~~~~~
drivers/staging/rtl8723bs/hal/hal_btcoex.c:23:26: warning:
‘BtSpecString’ defined but not used [-Wunused-const-variable=]
 static const char *const BtSpecString[] = {
                          ^~~~~~~~~~~~
drivers/staging/rtl8723bs/hal/hal_btcoex.c:15:26: warning:
‘BtProfileString’ defined but not used [-Wunused-const-variable=]
 static const char *const BtProfileString[] = {
                          ^~~~~~~~~~~~~~~

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20200417073310.40893-1-yanaijie@huawei.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>