breakage with "switch to gdb version script"

[Hans-Peter Nilsson <hans-peter.nilsson@axis.com>]

This commit:

commit 8c32ba22334b8be1c2cf412a789deeded786e1f5
Author: Mike Frysinger <vapier@gentoo.org>
Date:   Fri Apr 10 19:40:54 2015 -0400

    sim: switch to gdb version script
    
    Since the local create-version.sh already points directly into the gdb
    source tree, we might as well use the gdb script directly too.

 sim/common/ChangeLog         |    5 +++++
 sim/common/Make-common.in    |    5 +++--
 sim/common/create-version.sh |   38 --------------------------------------
 3 files changed, 8 insertions(+), 40 deletions(-)

seems to have caused breakage building a sim for
powerpc-unknown-eabisim:

...
make[3]: *** No rule to make target `/tmp/hpautotest-sim/src/sim/ppc/../common/create-version.sh', needed by `version.c'.  Stop.
make[3]: Leaving directory `/tmp/hpautotest-sim/powerpc-eabisim/sim/ppc'
make[2]: *** [all] Error 1make[2]: Leaving directory `/tmp/hpautotest-sim/powerpc-eabisim/sim'

While that seems pretty trivial, you also need to adjust
src-release.sh to make sure "./src-release.sh -b sim" works,
in which a tool-specific create-version.sh is searched.

brgds, H-P