make: Add scripts/utilities.mak

Some features need to be tested on the system
where the project is compiled, so instead of
drowning into autoconf hell lets try to handle
all this with make facility.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

scripts/utilities.mak

+# try-cc
+# Usage: option = $(call try-cc, source-to-build, cc-options)
+try-cc = $(shell sh -c						  \
+	'TMP="$(OUTPUT)$(TMPOUT).$$$$";				  \
+	 echo "$(1)" |						  \
+	 $(CC) -x c - $(2) -o "$$TMP" > /dev/null 2>&1 && echo y; \
+	 rm -f "$$TMP"')
+
+# try-build
+# Usage: option = $(call try-build, source-to-build, cc-options, link-options)
+try-build = $(shell sh -c							\
+	'TMP="$(OUTPUT)$(TMPOUT).$$$$";						\
+	echo "$(1)" |								\
+	$(CC) -x c - $(2) $(3) -o "$$TMP" > /dev/null 2>&1 && echo y;		\
+	rm -f "$$TMP"')