nb/intel/ironlake/raminit_heci.c: Move to southbridge scope

HECI stuff is in the southbridge, so put the code in there. Rename the
file to match the name of the function it provides.

Change-Id: I71de1234547dbd46a9b4959c619d2ae194da620a
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/61931
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/southbridge/intel/ibexpeak/me.h b/src/southbridge/intel/ibexpeak/me.h
index 4eea0af..8ff5ca7 100644
--- a/src/southbridge/intel/ibexpeak/me.h
+++ b/src/southbridge/intel/ibexpeak/me.h
@@ -231,6 +231,8 @@
 int intel_early_me_uma_size(void);
 int intel_early_me_init_done(u8 status);
 
+void setup_heci_uma(u64 heci_uma_addr, unsigned int heci_uma_size);
+
 typedef struct {
 	u32       major_version  : 16;
 	u32       minor_version  : 16;