runtime: no need to convert 'c.fault()' to uintptr in sighandler

After CL 528817, *sigctxt.fault of all arches return uintptr, so
there is no need to convert 'c.fault()' to uintptr anymore.

Change-Id: I062283b578adaaee69d8f439b109a573eeb15110
GitHub-Last-Rev: 3ce3a75
GitHub-Pull-Request: #63133
Reviewed-on: https://go-review.googlesource.com/c/go/+/529995
Reviewed-by: Ian Lance Taylor <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Auto-Submit: Ian Lance Taylor <[email protected]>
Reviewed-by: Michael Pratt <[email protected]>

Author: callthingsoff

src/runtime/signal_unix.go

@@ -698,7 +698,7 @@ func sighandler(sig uint32, info *siginfo, ctxt unsafe.Pointer, gp *g) {
 		// the unwinding code.
 		gp.sig = sig
 		gp.sigcode0 = uintptr(c.sigcode())
-		gp.sigcode1 = uintptr(c.fault())
+		gp.sigcode1 = c.fault()
 		gp.sigpc = c.sigpc()
 
 		c.preparePanic(sig, gp)