linux-user, scripts: add a script to update syscall.tbl

scripts/update-syscalltbl.sh has the list of syscall.tbl to update and
can copy them from the linux source directory

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200310103403.3284090-19-laurent@vivier.eu>
Signed-off-by: Laurent Vivier <laurent@vivier.eu>
diff --git a/MAINTAINERS b/MAINTAINERS
index 36d0c68..7098327 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2448,6 +2448,7 @@
 F: linux-user/
 F: default-configs/*-linux-user.mak
 F: scripts/qemu-binfmt-conf.sh
+F: scripts/update-syscalltbl.sh
 
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