staging: rtl8188eu: Use proper enum in rtl8188eu_config_rf_reg

staging: rtl8188eu: Use proper enum in rtl8188eu_config_rf_reg

Clang warns when an enumerated type is implicitly converted to another.

drivers/staging/rtl8188eu/hal/rf_cfg.c:180:25: warning: implicit
conversion from enumeration type 'enum rf90_radio_path' to different
enumeration type 'enum rf_radio_path' [-Wenum-conversion]
        rtl_rfreg_delay(adapt, RF90_PATH_A, addr | maskforphyset,
        ~~~~~~~~~~~~~~~        ^~~~~~~~~~~
1 warning generated.

Avoid this by using the equivalent value from the expected type,
rf_radio_path:

RF90_PATH_A = RF_PATH_A = 0

Link: https://github.com/ClangBuiltLinux/linux/issues/164
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>