mainboard/google/kahlee: Don't use AMD's secure OS

Disable the use of AMD's Secure OS through the Kconfig option.

BUG=chromium:903833
TEST=Build google/aleena, verify types 02, 0c, 0d are removed
from PSP directory table

Signed-off-by: Martin Roth <martinroth@chromium.org>
Change-Id: Iabb0632eef88170dde45dea2e2e15b54b3a06f7b
Reviewed-on: https://review.coreboot.org/c/coreboot/+/31890
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Richard Spiegel <richard.spiegel@silverbackltd.com>

src/mainboard/google/kahlee/Kconfig

@@ -141,4 +141,8 @@ config OEM_BIN_FILE
 	depends on USE_OEM_BIN
 	default ""
 
+# Don't use AMD's Secure OS
+config USE_PSPSECUREOS
+	def_bool n
+
 endif # BOARD_GOOGLE_BASEBOARD_KAHLEE