MAINTAINERS: Add qemu-binfmt-conf.sh script

qemu-binfmt-conf.sh is used for the Linux usermode emulation, so
let's add this file to that section in the MAINTAINERS file.
Signed-off-by: NThomas Huth <thuth@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>
Reviewed-by: NLaurent Vivier <laurent@vivier.eu>

MAINTAINERS

@@ -1761,6 +1761,7 @@ R: Laurent Vivier <laurent@vivier.eu>
 S: Maintained
 F: linux-user/
 F: default-configs/*-linux-user.mak
+F: scripts/qemu-binfmt-conf.sh
 
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