fix function signature of qemu_chr_open_pty on !linux

Signed-off-By: Riku Voipio <riku.voipio@nokia.com>
Signed-off-By: Juha Riihimäki <juha.riihimaki@nokia.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
diff --git a/qemu-char.c b/qemu-char.c
index 048da3f..c819863 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -1220,7 +1220,7 @@
     return chr;
 }
 #else  /* ! __linux__ && ! __sun__ */
-static CharDriverState *qemu_chr_open_pty(void)
+static CharDriverState *qemu_chr_open_pty(QemuOpts *opts)
 {
     return NULL;
 }