README.rst: let coverity badge point to the right project
README.rst: let coverity badge point to the right project

5085 is jluebbe/rauc while 22299 is rauc/rauc.

Signed-off-by: Enrico Joerns <a2e5f936c390f36494e46e71bcfbe365bb1e8c49@pengutronix.de>

jluebbe/rauc,rauc/rauc,ejoerns/rauc,jluebbe/rauc,ejoerns/rauc,ejoerns/rauc,jluebbe/rauc,rauc/rauc,rauc/rauc