lib: test_scanf: Add tests for sscanf number conversion

Adds test_sscanf to test various number conversion cases, as
number conversion was previously broken.

This also tests the simple_strtoxxx() functions exported from
vsprintf.c.
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210514161206.30821-3-rf@opensource.cirrus.com

MAINTAINERS

@@ -19395,6 +19395,7 @@ S:	Maintained
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk.git
 F:	Documentation/core-api/printk-formats.rst
 F:	lib/test_printf.c
+F:	lib/test_scanf.c
 F:	lib/vsprintf.c
 
 VT1211 HARDWARE MONITOR DRIVER

lib/Kconfig.debug

@@ -2163,6 +2163,9 @@ config TEST_KSTRTOX
 config TEST_PRINTF
 	tristate "Test printf() family of functions at runtime"
 
+config TEST_SCANF
+	tristate "Test scanf() family of functions at runtime"
+
 config TEST_BITMAP
 	tristate "Test bitmap_*() family of functions at runtime"
 	help

lib/Makefile

@@ -83,6 +83,7 @@ obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
 obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_keys.o
 obj-$(CONFIG_TEST_STATIC_KEYS) += test_static_key_base.o
 obj-$(CONFIG_TEST_PRINTF) += test_printf.o
+obj-$(CONFIG_TEST_SCANF) += test_scanf.o
 obj-$(CONFIG_TEST_BITMAP) += test_bitmap.o
 obj-$(CONFIG_TEST_STRSCPY) += test_strscpy.o
 obj-$(CONFIG_TEST_UUID) += test_uuid.o