lib/crc: tests: Add CRC_ENABLE_ALL_FOR_KUNIT

Now that crc_kunit uses the standard "depends on" pattern, enabling the
full set of CRC tests is a bit difficult, mainly due to CRC7 being
rarely used.  Add a kconfig option to make it easier.  It is visible
only when KUNIT, so hopefully the extra prompt won't be too annoying.

Link: https://lore.kernel.org/r/20260306033557.250499-3-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

Author: Eric Biggers

lib/crc/Kconfig

@@ -107,6 +107,20 @@ config CRC_KUNIT_TEST
 	  This is intended to help people writing architecture-specific
 	  optimized versions.  If unsure, say N.
 
+config CRC_ENABLE_ALL_FOR_KUNIT
+	tristate "Enable all CRC functions for KUnit test"
+	depends on KUNIT
+	select CRC7
+	select CRC16
+	select CRC_T10DIF
+	select CRC32
+	select CRC64
+	help
+	  Enable all CRC functions that have test code in CRC_KUNIT_TEST.
+
+	  Enable this only if you'd like the CRC KUnit test suite to test all
+	  the CRC variants, even ones that wouldn't otherwise need to be built.
+
 config CRC_BENCHMARK
 	bool "Benchmark for the CRC functions"
 	depends on CRC_KUNIT_TEST