3rdparty: Move to blobs

To move 3rdparty to 3rdparty/blobs (ie. below itself
from git's broken perspective), we need to work around
it - since some git implementations don't like the direct
approach.

Change-Id: I1fc84bbb37e7c8c91ab14703d609a739b5ca073c
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Reviewed-on: http://review.coreboot.org/10108
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

.gitmodules

@@ -1,5 +1,5 @@
 [submodule "3rdparty"]
-	path = 3rdparty
+	path = blobs
 	url = ../blobs.git
 	update = none
 	ignore = dirty