x/sys/unix: add type specific ioctl functions for termios on solaris

The existing code has no way to manipulate termios or winsize structures
on solaris.  This change adds IoctlGetXXX and IoctlSetXXX functions for
int, termios, termio, and winsize.  The embedded awk script in
mkerrors.sh has additional patterns to generate the needed ioctl
constants for these calls.

Fixes golang/go#12574

Change-Id: Ic62a8c698d42c8ca379c90f71e9f27635e7d03b5
Reviewed-on: https://go-review.googlesource.com/14587
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Aram Hăvărneanu <aram@mgk.ro>

unix/zsyscall_solaris_amd64.go

@@ -22,6 +22,7 @@ import (
 //go:cgo_import_dynamic libc_recvmsg recvmsg "libsocket.so"
 //go:cgo_import_dynamic libc_sendmsg sendmsg "libsocket.so"
 //go:cgo_import_dynamic libc_acct acct "libc.so"
+//go:cgo_import_dynamic libc_ioctl ioctl "libc.so"
 //go:cgo_import_dynamic libc_access access "libc.so"
 //go:cgo_import_dynamic libc_adjtime adjtime "libc.so"
 //go:cgo_import_dynamic libc_chdir chdir "libc.so"
@@ -136,6 +137,7 @@ import (
 //go:linkname procrecvmsg libc_recvmsg
 //go:linkname procsendmsg libc_sendmsg
 //go:linkname procacct libc_acct
+//go:linkname procioctl libc_ioctl
 //go:linkname procAccess libc_access
 //go:linkname procAdjtime libc_adjtime
 //go:linkname procChdir libc_chdir
@@ -251,6 +253,7 @@ var (
 	procrecvmsg,
 	procsendmsg,
 	procacct,
+	procioctl,
 	procAccess,
 	procAdjtime,
 	procChdir,
@@ -472,6 +475,14 @@ func acct(path *byte) (err error) {
 	return
 }
 
+func ioctl(fd int, req int, arg uintptr) (err error) {
+	_, _, e1 := sysvicall6(uintptr(unsafe.Pointer(&procioctl)), 3, uintptr(fd), uintptr(req), uintptr(arg), 0, 0, 0)
+	if e1 != 0 {
+		err = e1
+	}
+	return
+}
+
 func Access(path string, mode uint32) (err error) {
 	var _p0 *byte
 	_p0, err = BytePtrFromString(path)