src/Makefile: include CFLAGS in probe macros

When cross-building we need to pass the correct paths via CFLAGS to be
able to find extra libraries. We could convert to using pkg-config to
resolve library availability but as the rest of the build doesn't need
it we can just ensure the same CFLAGS used for building are used in
the probe macros.

Signed-off-by: Alex Bennée <[email protected]>

Author: stsquad

src/Makefile

@@ -1,11 +1,11 @@
 H := \#
 
 HAVE_C_HEADER = $(shell if echo "$(H)include <$(1)>" |		\
-		$(CC) -E - > /dev/null 2>&1; then echo "$(2)";	\
+		$(CC) $(CFLAGS) -E - > /dev/null 2>&1; then echo "$(2)";	\
 		else echo "$(3)"; fi)
 
 HAVE_C_MACRO = $(shell if echo "$(H)include <$(1)>" |	\
-		$(CC) -E - 2>&1 /dev/null | grep $(2) > /dev/null 2>&1; \
+		$(CC) $(CFLAGS) -E - 2>&1 /dev/null | grep $(2) > /dev/null 2>&1; \
 		then echo 1;else echo 0; fi)
 
 C_TARGETS := \