build: use AX_IS_RELEASE() and AX_COMPILER_FLAGS()

The autoconf macros AX_COMPILER_FLAGS_{CFLAGS|GIR|LDFLAGS} test
for compiler and linker support of various flags, and add the flags to
the generated output.

If the command-line option '--enable-compile-warnings' is specified to
'configure', a number of additional warning options is also added to the
output. This is the default.

This update requires the presence of the GNU autoconf-archive in the
system.

test/Makefile.am

@@ -2,6 +2,14 @@
 noinst_PROGRAMS =
 EXTRA_DIST =
 
+AM_CFLAGS = \
+	$(WARN_CFLAGS) \
+	$(NULL)
+
+AM_LDFLAGS = \
+	$(WARN_LDFLAGS) \
+	$(NULL)
+
 ################################################################################
 # lsudev
 ################################################################################