runtime: treat SIGTSTP/SIGCANCEL on Solaris as we do on GNU/Linux

Change-Id: I617abd53f5fc883b972a1ef090886b85607e00bb
Reviewed-on: https://go-review.googlesource.com/18155Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>

src/runtime/signal_solaris.go

@@ -34,7 +34,7 @@ var sigtable = [...]sigTabT{
 	/* 21 */ {_SigNotify, "SIGURG: urgent socket condition"},
 	/* 22 */ {_SigNotify, "SIGPOLL: pollable event occured"},
 	/* 23 */ {_SigNotify + _SigDefault, "SIGSTOP: stop (cannot be caught or ignored)"},
-	/* 24 */ {0, "SIGTSTP: user stop requested from tty"},
+	/* 24 */ {_SigNotify + _SigDefault, "SIGTSTP: user stop requested from tty"},
 	/* 25 */ {0, "SIGCONT: stopped process has been continued"},
 	/* 26 */ {_SigNotify + _SigDefault, "SIGTTIN: background tty read attempted"},
 	/* 27 */ {_SigNotify + _SigDefault, "SIGTTOU: background tty write attempted"},
@@ -46,7 +46,7 @@ var sigtable = [...]sigTabT{
 	/* 33 */ {_SigNotify, "SIGLWP: reserved signal no longer used by"},
 	/* 34 */ {_SigNotify, "SIGFREEZE: special signal used by CPR"},
 	/* 35 */ {_SigNotify, "SIGTHAW: special signal used by CPR"},
-	/* 36 */ {0, "SIGCANCEL: reserved signal for thread cancellation"}, // Oracle's spelling of cancelation.
+	/* 36 */ {_SigSetStack + _SigUnblock, "SIGCANCEL: reserved signal for thread cancellation"}, // Oracle's spelling of cancelation.
 	/* 37 */ {_SigNotify, "SIGLOST: resource lost (eg, record-lock lost)"},
 	/* 38 */ {_SigNotify, "SIGXRES: resource control exceeded"},
 	/* 39 */ {_SigNotify, "SIGJVM1: reserved signal for Java Virtual Machine"},