Revert "Support Boehm GC 7.2" (w3m-0.5.2-gc72.patch from Gentoo)

This reverts commit 4331db3e3e673ac4dbfe8e9f2b42a8e0478dc98a.
Support Boehm GC 7.2

Replace Gentoo's patch to prevent segfaults due to infinite recursion.

Origin: https://bugs.debian.org/cgi-bin/bugreport.cgi?msg=5;filename=080_gc72.patch;att=1;bug=758831
Bug-Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=758831
Bug-Fedora: https://bugzilla.redhat.com/show_bug.cgi?id=555467
Bug: http://sourceforge.net/p/w3m/patches/63/
Bug: http://sourceforge.net/p/w3m/patches/59/
Merge branch 'bug/gc72'
Update config.sub to 2014-05-01 with autotools-dev 20140510.1
Update config.guess to 2014-03-23 with autotools-dev 20140510.1
Merge branch 'bug/autotools-config'
Update to 0.5.3+debian-17
Merge branch 'feature/debian-version'
Update ChangeLog
Merge branch 'bug/changelog'