x86: Rename some FSP functions to have an fsp_ prefix

Given these exported function an fsp_ prefix since they are declared in an
fsp.h header.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Tested-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/cmd/x86/fsp.c b/cmd/x86/fsp.c
index fb27624..b3b6630 100644
--- a/cmd/x86/fsp.c
+++ b/cmd/x86/fsp.c
@@ -11,7 +11,7 @@
 
 static int do_hdr(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 {
-	struct fsp_header *hdr = find_fsp_header();
+	struct fsp_header *hdr = fsp_find_header();
 	u32 img_addr = hdr->img_base;
 	char *sign = (char *)&hdr->sign;
 	int i;