coreutils: removed config cache injection of 'gl_cv_func_re_compile_pattern_working=yes'

Note:

This seems to be glibc specific, breaking the build when using musl libc as
default libc.

base/coreutils/coreutils.conf

@@ -32,7 +32,6 @@ hostcc_make_prime_list() {
 
 if atstage cross; then
 	# http://bugs.gentoo.org/show_bug.cgi?id=269256
-	var_append configcache ' ' 'gl_cv_func_re_compile_pattern_working=yes'
 	var_append configcache ' ' 'gl_cv_func_rename_trailing_dest_slash_bug=no'
 	var_append configcache ' ' 'gl_cv_func_rename_trailing_slash_bug=no'