rawspeed: update to svn r588 (thanks klaus)
(cherry picked from commit 3c7a6bbbbcdd3cd5f0a551b2072e9697d86e9e54)
rawspeed: add back aspect ratio support for the Pana DMC-G6 and minor tweak for DMC-GH3
(cherry picked from commit 32d68ef84be3cf50b2cf8241aa0421a342f78cdf)