baremetal-helloworld: Update SRCREV to fix entry addresses for ARM architectures

Update to the latest SRCREV to bring fixes using the proper entry
addresses for ARM architectures [1], as well as fixing a race condition
in the Makefile during assembly [2].

Fix url in case automatic redirects stop working.

[1] https://github.com/ahcbb6/baremetal-helloqemu/commit/602e82aee7ae95ee50eedb7f40c4a225ec5a3fb9
[2] https://github.com/ahcbb6/baremetal-helloqemu/commit/ea7f59b02467ed1fb36c3b4c6d5cabe702df26ec



Signed-off-by: Alejandro Enedino Hernandez Samaniego <alejandro@enedino.org>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>