intel/e7505,i82801dx: Fix SMM_ASEG lock

In our codebase, this is only coupled with intel/e7505.
The PCI registers reference here were for intel/i945.

Also aseg_smm_lock() was previously not called.

Change-Id: I21d991c8c2f5c2dde1f148fd80963e39d9836d3c
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34149
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/northbridge/intel/e7505/memmap.c

@@ -35,6 +35,14 @@ void *cbmem_top(void)
 	return (void *)tolm;
 }
 
+void northbridge_write_smram(u8 smram);
+
+void northbridge_write_smram(u8 smram)
+{
+	pci_devfn_t mch = PCI_DEV(0, 0, 0);
+	pci_write_config8(mch, SMRAMC, smram);
+}
+
 /* platform_enter_postcar() determines the stack to use after
  * cache-as-ram is torn down as well as the MTRR settings to use,
  * and continues execution in postcar stage. */