The following patch fixes

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82353

LRA did not update hard reg liveness on bb borders for hard regs which 
are part of insn patterns like CFLAGS reg.  It was ok for inheritance in 
EBB which creates only moves and they usually have no embedded hard regs 
in the patterns.  But LRA rematerialization needs this.  So this patch 
implements such hard reg liveness updates.

The patch was successfully bootstrapped and tested on x86-64.

Committed as rev. 253656.