gitver: fix try/except syntax for python3 support

https://www.python.org/dev/peps/pep-3110/

It's backward compatible with 2.6+

Signed-off-by: Alejandro Mery <amery@hanoverdisplays.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

meta-oe/classes/gitver.bbclass

@@ -27,13 +27,13 @@ def get_git_pv(path, d, tagadjust=None):
     gitdir = os.path.abspath(os.path.join(d.getVar("S", True), ".git"))
     try:
         ver = gitrev_run("git describe --tags", gitdir)
-    except Exception, exc:
+    except Exception as exc:
         bb.fatal(str(exc))
 
     if not ver:
         try:
             ver = gitrev_run("git rev-parse --short HEAD", gitdir)
-        except Exception, exc:
+        except Exception as exc:
             bb.fatal(str(exc))
 
         if ver: