staging: r8188eu: convert rtw_p2p_get_req_cm to return void

rtw_p2p_get_req_cm always returns 0 and it's return value is not used.
Convert it to return void.

Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
Link: https://lore.kernel.org/r/a5940e6778431a4ce2d2e67543c59aae90464604.1643466748.git.abdun.nihaal@gmail.com


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