vendorcode/google/chromeos: remove unnecessary includes in elog.c

The elog.c file had stale includes no longer needed. Remove them.

BUG=chrome-os-partner:55932

Change-Id: I891a57d08281c3c56e9d35489d6dea6c47eaa27b
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/16085
Tested-by: build bot (Jenkins)
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/vendorcode/google/chromeos/elog.c

@@ -14,13 +14,9 @@
  */
 
 #include <bootstate.h>
-#include <cbmem.h>
 #include <console/console.h>
 #include <elog.h>
-#include <vendorcode/google/chromeos/chromeos.h>
-#include <vboot/vbnv.h>
 #include <vboot/vboot_common.h>
-#include <vboot_struct.h>
 
 static void elog_add_boot_reason(void *unused)
 {