x86: fsp_support: Correct high mem comment typo

High mem starts at 4 GiB.

Signed-off-by: Andrew Bradford <andrew.bradford@kodakalaris.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/fsp/fsp_support.c b/arch/x86/lib/fsp/fsp_support.c
index 5f96da1..5809235 100644
--- a/arch/x86/lib/fsp/fsp_support.c
+++ b/arch/x86/lib/fsp/fsp_support.c
@@ -279,7 +279,7 @@
 			res_desc = (struct hob_res_desc *)hdr;
 			if (res_desc->type == RES_SYS_MEM) {
 				phys_start = res_desc->phys_start;
-				/* Need memory above 1MB to be collected here */
+				/* Need memory above 4GB to be collected here */
 				if (phys_start >= (phys_addr_t)FSP_HIGHMEM_BASE)
 					top += (u32)(res_desc->len);
 			}