smbios: Use char consistently for the eos member

At present a few of the structs use u8 instead of char. This is a string,
so char is better. Update them.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/include/smbios.h b/include/smbios.h
index fc69188..1cbeabf 100644
--- a/include/smbios.h
+++ b/include/smbios.h
@@ -183,14 +183,14 @@
 	u16 handle;
 	u8 reserved[6];
 	u8 boot_status;
-	u8 eos[SMBIOS_STRUCT_EOS_BYTES];
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
 };
 
 struct __packed smbios_type127 {
 	u8 type;
 	u8 length;
 	u16 handle;
-	u8 eos[SMBIOS_STRUCT_EOS_BYTES];
+	char eos[SMBIOS_STRUCT_EOS_BYTES];
 };
 
 struct __packed smbios_header {