nb/intel/sandybridge: Drop pch.h from sandybridge.h

Include pch.h in the source files instead in sandybridge.h.

Tested on Lenovo T520 (Intel Sandy Bridge).
Still boots to OS, no errors visible in dmesg.

Change-Id: I9e5b678e979a8d136d8d00b49486d0a882f77d81
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32065
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/mainboard/intel/dcp847ske/romstage.c b/src/mainboard/intel/dcp847ske/romstage.c
index 24ec912..235ad22 100644
--- a/src/mainboard/intel/dcp847ske/romstage.c
+++ b/src/mainboard/intel/dcp847ske/romstage.c
@@ -23,6 +23,7 @@
 #else
 #include <northbridge/intel/sandybridge/raminit.h>
 #endif
+#include <southbridge/intel/bd82x6x/pch.h>
 
 #if !CONFIG(USE_NATIVE_RAMINIT)
 void mainboard_fill_pei_data(struct pei_data *pei_data)