soc/amd: Add picasso to Kconfig

Change-Id: I7031b07ae105a14be3c5d4e52ecc1364956fd845
Signed-off-by: Marshall Dawson <marshalldawson3rd@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33750
Reviewed-by: Richard Spiegel <richard.spiegel@silverbackltd.com>
Reviewed-by: Edward O'Callaghan <quasisec@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/Kconfig

@@ -1,4 +1,5 @@
 # Load all chipsets before common
+source "src/soc/amd/picasso/Kconfig"
 source "src/soc/amd/stoneyridge/Kconfig"
 
 # Load common defaults last