tests: sprintf: convert normal test to use ztest

This patch convert net test cases to use ztest framework APIs
which makes output unified to other test cases.

Signed-off-by: Punit Vara <punit.vara@intel.com>

tests/kernel/sprintf/prj.conf

@@ -2,3 +2,4 @@ CONFIG_STDOUT_CONSOLE=y
 CONFIG_NUM_IRQS=2
 CONFIG_FLOAT=y
 CONFIG_MAIN_STACK_SIZE=2048
+CONFIG_ZTEST=y

tests/kernel/sprintf/src/Makefile

@@ -1,3 +1,4 @@
 ccflags-y += -I${ZEPHYR_BASE}/tests/include
+include ${ZEPHYR_BASE}/tests/Makefile.test
 
-obj-y = test_sprintf.o
+obj-y = test_sprintf.o main.o

tests/kernel/sprintf/src/main.c

@@ -0,0 +1,36 @@
+/*
+ * Copyright (c) 2017 Intel Corporation
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/**
+ * @addtogroup t_kernel_sprintf
+ * @{
+ * @defgroup t_sprintf_api test_sorintf_fn
+ * @}
+ */
+
+#include <ztest.h>
+extern void sprintf_double_test(void);
+extern void vsnprintf_test(void);
+extern void vsprintf_test(void);
+extern void snprintf_test(void);
+extern void sprintf_misc_test(void);
+extern void sprintf_integer_test(void);
+extern void sprintf_stringtest(void);
+
+/*test case main entry*/
+void test_main(void *p1, void *p2, void *p3)
+{
+	ztest_test_suite(test_sprintf_fn,
+		ztest_unit_test(sprintf_double_test),
+		ztest_unit_test(vsnprintf_test),
+		ztest_unit_test(vsprintf_test),
+		ztest_unit_test(snprintf_test),
+		ztest_unit_test(sprintf_misc_test),
+		ztest_unit_test(sprintf_integer_test),
+		ztest_unit_test(sprintf_stringtest));
+
+	ztest_run_test_suite(test_sprintf_fn);
+}