Integrate changes #12652 and #12653 from maintperl;

Integrate changes #12652 and #12653 from maintperl;

more tweaks to change#12626
* move the boilerplate code over to perl.h and make DynaLoader
  use it
* make re, Opcode, File::Glob and B threadsafe
* re.xs needed s/deinstall/uninstall/ (guess nobody uses
  C<no re;> anywhere)

include XS_VERSION in MY_CXT_KEY (tweak for change#12652)

File::Glob required a bit more work in bleadperl
because of ExtUtils::Constant (see the Makefile.PL change)

p4raw-link: @12652 on //depot/maint-5.6/perl: 3bc8871b91a24662eada2114d9a016153718b1c4
p4raw-link: @12626 on //depot/maint-5.6/perl: 512dcce54ea4db665708f91609bdd0a6126d1acd

p4raw-id: //depot/perl@12654
p4raw-integrated: from //depot/maint-5.6/perl@12650 'edit in'
	ext/B/B.xs ext/DynaLoader/dlutils.c (@12652..) 'merge in'
	perl.h (@12597..) ext/File/Glob/Glob.xs ext/Opcode/Opcode.xs
	ext/re/re.xs (@12652..)