runtime: call sigtrampgo on solaris

CL 57291 broke on solaris because it depends on signal forwarding
working for signals raised by dieFromSignal.
Call sigtrampgo instead of sighandler directly, like the other
unix platforms.

Fixes the solaris builders.

Change-Id: I6bf314c436d1edeaecc4b03f15a9155270919524
Reviewed-on: https://go-review.googlesource.com/59811
Run-TryBot: Elias Naur <elias.naur@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/runtime/sys_solaris_amd64.s

@@ -183,9 +183,6 @@ TEXT runtime·sigtramp(SB),NOSPLIT,$0
 	JMP	exit
 
 allgood:
-	// save g
-	MOVQ	R10, 80(SP)
-
 	// Save m->libcall and m->scratch. We need to do this because we
 	// might get interrupted by a signal in runtime·asmcgocall.
 
@@ -223,19 +220,11 @@ allgood:
 	MOVL	0(R10), R10
 	MOVQ	R10, 160(SP)
 
-	MOVQ	g(BX), R10
-	// g = m->gsignal
-	MOVQ	m_gsignal(BP), BP
-	MOVQ	BP, g(BX)
-
-	// TODO: If current SP is not in gsignal.stack, then adjust.
-
 	// prepare call
 	MOVQ	DI, 0(SP)
 	MOVQ	SI, 8(SP)
 	MOVQ	DX, 16(SP)
-	MOVQ	R10, 24(SP)
-	CALL	runtime·sighandler(SB)
+	CALL	runtime·sigtrampgo(SB)
 
 	get_tls(BX)
 	MOVQ	g(BX), BP
@@ -273,10 +262,6 @@ allgood:
 	MOVQ	160(SP), R10
 	MOVL	R10, 0(R11)
 
-	// restore g
-	MOVQ	80(SP), R10
-	MOVQ	R10, g(BX)
-
 exit:
 	// restore registers
 	MOVQ	32(SP), BX