fix toolchain build on darwin, avoid (a|), which seems to be not documented in POSIX

toolchain/glibc/patches/sparc-darwin.patch

@@ -0,0 +1,12 @@
+diff -Nur glibc-2.19.orig/configure glibc-2.19/configure
+--- glibc-2.19.orig/configure	2014-02-07 10:04:38.000000000 +0100
++++ glibc-2.19/configure	2014-04-16 23:11:01.000000000 +0200
+@@ -6228,7 +6228,7 @@
+   $as_echo "$as_me:${as_lineno-$LINENO}: \$? = $ac_status" >&5
+   test $ac_status = 0; }; }
+ then
+-  if $READELF -S conftest.so | grep '\.rel\(a\|\)\.dyn' > /dev/null; then
++  if $READELF -S conftest.so | grep '\.\(rela\|rel\)\.dyn' > /dev/null; then
+     libc_cv_z_combreloc=yes
+   else
+     libc_cv_z_combreloc=no