staging: rtl8723bs: remove unused variables

A cleanup patch removed the only user of two local variables:

drivers/staging/rtl8723bs/hal/hal_btcoex.c: In function 'hal_btcoex_Initialize':
drivers/staging/rtl8723bs/hal/hal_btcoex.c:1415:5: error: unused variable 'ret2' [-Werror=unused-variable]
drivers/staging/rtl8723bs/hal/hal_btcoex.c:1414:5: error: unused variable 'ret1' [-Werror=unused-variable]

This removes the declarations as well.

Fixes: 95b3b423 ("staging: rtl8723bs: remove ternary operators in assignmet statments")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>