maintainers: Add myself as a OpenBSD maintainer

Add myself as an OpenBSD maintainer and add OpenBSD as maintained.

Signed-off-by: Brad Smith <brad@comstyle.com>
Reviewed-by: Kamil Rytarowski <n54@gmx.com>
Message-id: 20180216164620.GA53727@humpty.home.comstyle.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

MAINTAINERS

@@ -386,6 +386,12 @@ M: Kamil Rytarowski <kamil@netbsd.org>
 S: Maintained
 K: ^Subject:.*(?i)NetBSD
 
+OPENBSD
+L: qemu-devel@nongnu.org
+M: Brad Smith <brad@comstyle.com>
+S: Maintained
+K: ^Subject:.*(?i)OpenBSD
+
 W32, W64
 L: qemu-devel@nongnu.org
 M: Stefan Weil <sw@weilnetz.de>

configure

@@ -760,6 +760,7 @@ OpenBSD)
   audio_drv_list="sdl"
   audio_possible_drivers="sdl"
   HOST_VARIANT_DIR="openbsd"
+  supported_os="yes"
 ;;
 Darwin)
   bsd="yes"