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

 --- gcc-4.3.4/libffi/src/arm/sysv.S	

 +++ gcc-4.3.4/libffi/src/arm/sysv.S	

 @@ -235,7 +235,7 @@ ARM_FUNC_START ffi_closure_SYSV

  	stmfd	sp!, {ip, lr}

  	UNWIND .save	{r0, lr}

  	add	r2, sp, #8

 -	.pad #16

 +	UNWIND .pad #16

  	sub	sp, sp, #16

  	str	sp, [sp, #8]

  	add	r1, sp, #8