sed portability fixes in fixincludes

fixincludes/:
	PR testsuite/29737
	PR bootstrap/35938
	PR testsuite/39655
	* check.tpl: Fix typos.
	* README: Likewise.  Also, document that 'select' uses ERE.
	* mkheaders.in: Update copyright years in --version output.
	* inclhack.def (sco_math): Add missing final newline in sed
	script 'a', 'c', or 'i' commands, for BSD sed.
	(sco_math): In the text of 'a', 'c', or 'i' sed
	commands, prepend leading white space with a backslash to avoid
	the whitespace to be removed by BSD sed.
	(sco_math): Match plain 'C++' instead of 'C\+\+' in sed regex.
	(x11_new): Fix sed expression, for BSD sed.
	(glibc_mutex_init): Fix newlines in sed 's' command replacement
	part, for GNU sed 3.02 and Solaris sed.
	(glibc_mutex_init): Replace unportable \+ sed regex operator
	with \{1,\}.
	(glibc_c99_inline_2, glibc_mutex_init): Avoid unportable sed
	alternation \| regex operator.
	(solaris_complex): Remove superfluous backslashes from
	replacement string.  Replace \+ operator with \{1,\}.
	* tests/base/Xm/Traversal.h: This is fixed for BSD sed now.
	* fixincl.x: Regenerate.

From-SVN: r151518