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/test/print_ut.c b/test/print_ut.c
index 0bc548d..a3b9974 100644
--- a/test/print_ut.c
+++ b/test/print_ut.c
@@ -15,6 +15,26 @@
 #define FAKE_BUILD_TAG	"jenkins-u-boot-denx_uboot_dm-master-build-aarch64" \
 			"and a lot more text to come"
 
+/* Test printing GUIDs */
+static void guid_ut_print(void)
+{
+#if CONFIG_IS_ENABLED(LIB_UUID)
+	unsigned char guid[16] = {
+		1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16
+	};
+	char str[40];
+
+	sprintf(str, "%pUb", guid);
+	assert(!strcmp("01020304-0506-0708-090a-0b0c0d0e0f10", str));
+	sprintf(str, "%pUB", guid);
+	assert(!strcmp("01020304-0506-0708-090A-0B0C0D0E0F10", str));
+	sprintf(str, "%pUl", guid);
+	assert(!strcmp("04030201-0605-0807-090a-0b0c0d0e0f10", str));
+	sprintf(str, "%pUL", guid);
+	assert(!strcmp("04030201-0605-0807-090A-0B0C0D0E0F10", str));
+#endif
+}
+
 /* Test efi_loader specific printing */
 static void efi_ut_print(void)
 {
@@ -117,6 +137,9 @@
 	/* Test efi_loader specific printing */
 	efi_ut_print();
 
+	/* Test printing GUIDs */
+	guid_ut_print();
+
 	printf("%s: Everything went swimmingly\n", __func__);
 	return 0;
 }