cmake.mk: set C/CXX compiler for host builds as well

Without this, cmake will use whatever CC/CXX is set to, which could be
clang. In that case, at least libjson-c/host will fail to compile.

Signed-off-by: Rosen Penev <rosenp@gmail.com>

include/cmake.mk

@@ -97,6 +97,8 @@ define Host/Configure/Default
 		LDFLAGS="$(HOST_LDFLAGS)" \
 		cmake \
 			-DCMAKE_BUILD_TYPE=Release \
+			-DCMAKE_C_COMPILER="$(HOSTCC)" \
+			-DCMAKE_CXX_COMPILER="$(HOSTCXX)" \
 			-DCMAKE_C_FLAGS_RELEASE="-DNDEBUG" \
 			-DCMAKE_CXX_FLAGS_RELEASE="-DNDEBUG" \
 			-DCMAKE_EXE_LINKER_FLAGS:STRING="$(HOST_LDFLAGS)" \