pseudo: Switch back to the master branch

OE is the main user of pseudo and we've had the changes in the oe-core branch
around long enough that we're going to run with them. Swicth back to directly
using the master branch.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
[Luca: re-add 'branch' parameter to fix "does not set any branch parameter" warning]
Signed-off-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>