x86: Add MultiProcessor (MP) table APIs

The MP table provides a way for the operating system to support
for symmetric multiprocessing as well as symmetric I/O interrupt
handling with the local APIC and I/O APIC. We provide a bunch of
APIs for U-Boot to write the floating table, configuration table
header as well as base and extended table entries.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>

arch/x86/include/asm/tables.h

@@ -27,6 +27,20 @@
  */
 u8 table_compute_checksum(void *v, int len);
 
+/**
+ * table_fill_string() - Fill a string with pad in the configuration table
+ *
+ * This fills a string in the configuration table. It copies number of bytes
+ * from the source string, and if source string length is shorter than the
+ * required size to copy, pad the table string with the given pad character.
+ *
+ * @dest:	where to fill a string
+ * @src:	where to copy from
+ * @n:		number of bytes to copy
+ * @pad:	character to pad the remaining bytes
+ */
+void table_fill_string(char *dest, const char *src, size_t n, char pad);
+
 /**
  * write_tables() - Write x86 configuration tables
  *