cmake LWS_HAVE_GETGRGID_R examples

warmcat/libwebsockets CMakeLists.txt :664 

CHECK_FUNCTION_EXISTS(getgrgid_r LWS_HAVE_GETGRGID_R)

c-jimenez/open-ocpp 3rdparty/libwebsockets/CMakeLists.txt :588 

CHECK_FUNCTION_EXISTS(getgrgid_r LWS_HAVE_GETGRGID_R)

fluffos/fluffos src/thirdparty/libwebsockets/CMakeLists.txt :571 

CHECK_FUNCTION_EXISTS(getgrgid_r LWS_HAVE_GETGRGID_R)