gdb-7.6.x:
 * add patch fixing (actually workarounding) "GDB bug: target.c (gdb_signal_from_host): unrecognized real-time signal"-problem
 * refs [https://sourceware.org/bugzilla/show_bug.cgi?id=14523 gdb-bug-14523], patch taken from OpenWrt


git-svn-id: file:///var/svn/freetz/trunk@11569 149334a1-2f27-0410-a3b9-fc62619ac1e6