configure.ac : Pass -fno-inline-small-functions when using GCC 4.7

For some reason, the build fails when using GCC 4.7 due to the implicit
-finline-functions option passed to the compiler when -O3 is enabled,
which does not happen in newer versions of GCC, probably due to some of
the "General Optimizer Improvements" included in 4.8 (see [1]).

Fortunately, we don't need to disable -finline-functions completely but
just do it for "small functions", which is what this patch does.

[1] https://gcc.gnu.org/gcc-4.8/changes.html

Closes: https://sourceforge.net/p/flac/bugs/429/
Signed-off-by: Erik de Castro Lopo <erikd@mega-nerd.com>

configure.ac

@@ -397,6 +397,10 @@ if test x$ac_cv_c_compiler_gnu = xyes ; then
 		XIPH_ADD_CFLAGS([-fgnu89-inline])
 		fi
 
+	if test "x$GCC_MAJOR_VERSION$GCC_MINOR_VERSION" = "x47" ; then
+		XIPH_ADD_CFLAGS([-fno-inline-small-functions])
+		fi
+
 	if test "x$asm_optimisation$sse_os" = "xyesyes" ; then
 		XIPH_ADD_CFLAGS([-msse2])
 		fi