libc/eglibc: fix missing LIBC_TRY_CC_OPTION definition (eglibc 2.15)

Upstream SVN is currently broken:
http://www.eglibc.org/svn/branches/eglibc-2_15/libc/

LIBC_TRY_CC_OPTION macro is not defined in aclocal.m4.
This patch fix the configure script.

Once upstream branch will be fixed this patch could be reverted.

Related patch (committed to eglibc trunk):
Use autoconf macro for testing compiler options with empty input
http://sourceware.org/ml/libc-alpha/2012-03/msg00816.html

Signed-off-by: Matthieu Crapet <mcrapet@gmail.com>

diff -r 1f6c8e4b2b92 -r d10afc5bcc25
patches/eglibc/2_15/110-aclocal-LIBC_TRY_CC_OPTION.patch

Fix for psim build failure due to -lz

See http://sourceware.org/bugzilla/show_bug.cgi?id=12202

--- gdb-7.2.orig/sim/ppc/Makefile.in

+++ gdb-7.2/sim/ppc/Makefile.in

@@ -551,7 +551,7 @@

 PACKAGE_OBJ = @sim_pk_obj@

-psim: $(TARGETLIB) main.o $(LIBIBERTY_LIB) $(BFD_LIB) $(LIBS) $(LIBINTL_DEP)

+psim: $(TARGETLIB) main.o $(LIBIBERTY_LIB) $(BFD_LIB) $(LIBINTL_DEP)

 	$(CC) $(CFLAGS) $(SIM_CFLAGS) $(LDFLAGS) -o psim$(EXEEXT) main.o $(TARGETLIB) $(BFD_LIB) $(LIBINTL) $(LIBIBERTY_LIB) $(LIBS)

 run: psim