[Patch, regex, libstdc++/69794] Unify special character parsing

[Jonathan Wakely]

On 15/02/16 20:41 -0800, Tim Shen wrote:
>    	PR libstdc++/69794
>    	* include/bits/regex_scanner.h: Add different special character
>    	sets for grep and egrep regex.
>    	* include/bits/regex_scanner.tcc: Use _M_spec_char more unifiedly.

s/unifiedly/uniformly/

OK for trunk and gcc-5-branch with that change, thanks for fixing the
regression.