Setting RF (resume flag) allows a debugger to resume execution after a
code breakpoint without tripping the breakpoint again.  It is reset by
the CPU after execution of one instruction.

Requested by Stephane Eranian:
  "I am trying to the user HW debug registers on i386 and I am running
   into a problem with ptrace() not allowing access to EFLAGS_RF for
   POKEUSER (see FLAG_MASK).  [ ...  ] It avoids the need to remove the
   breakpoint, single step, and reinstall.  The equivalent functionality
   exists on IA-64 and is allowed by ptrace()"

Cc: Stephane Eranian <eranian@hpl.hp.com>
Signed-off-by: Chuck Ebbert <76306.1226@compuserve.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>