CBMEM x86: Unify get_cbmem_toc()

Remove any chipset-specific implementations and use arch-specific
implementation of get_cbmem_table() instead.

Change-Id: I338ee2c1bd51f5e517462115170dc926e040159e
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: http://review.coreboot.org/3907
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@google.com>

src/include/cbmem.h

@@ -141,7 +141,7 @@ void cbmem_init(u64 baseaddr, u64 size);
 int cbmem_reinit(u64 baseaddr);
 
 void get_cbmem_table(uint64_t *base, uint64_t *size);
-extern struct cbmem_entry *get_cbmem_toc(void);
+struct cbmem_entry *get_cbmem_toc(void);
 
 #endif /* CONFIG_DYNAMIC_CBMEM */