lib/vsprintf: allow printing upper case GUIDs

In the UEFI context GUIDs are expected to be rendered in upper case.

The patch uses the formerly unused bit 1 of the parameter str_format
of function uuid_bin_to_str() to indicate if we need upper or lower case
output.

Function uuid_string() in vsprint.c is adjusted to correctly set the bit
depending on the print format code.

%pUb: 01020304-0506-0708-090a-0b0c0d0e0f10
%pUB: 01020304-0506-0708-090A-0B0C0D0E0F10
%pUl: 04030201-0605-0807-090a-0b0c0d0e0f10
%pUL: 04030201-0605-0807-090A-0B0C0D0E0F10

Up to this point only a diagnostic message in mount_ubifs() using '%pUB' is
concerned by the change. Further patches are needed to adjust the UEFI
subsystem.

A unit test is provided inside the ut_print command.

Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
diff --git a/include/uuid.h b/include/uuid.h
index 124bbce..abcc325 100644
--- a/include/uuid.h
+++ b/include/uuid.h
@@ -6,6 +6,8 @@
 #ifndef __UUID_H__
 #define __UUID_H__
 
+#include <linux/bitops.h>
+
 /* This is structure is in big-endian */
 struct uuid {
 	unsigned int time_low;
@@ -16,10 +18,10 @@
 	unsigned char node[6];
 } __packed;
 
-enum {
-	UUID_STR_FORMAT_STD,
-	UUID_STR_FORMAT_GUID
-};
+/* Bits of a bitmask specifying the output format for GUIDs */
+#define UUID_STR_FORMAT_STD	0
+#define UUID_STR_FORMAT_GUID	BIT(0)
+#define UUID_STR_UPPER_CASE	BIT(1)
 
 #define UUID_STR_LEN		36
 #define UUID_BIN_LEN		sizeof(struct uuid)