firmware: cs_dsp: Fix endianness conversion in cs_dsp_mock_wmfw.c

In cs_dsp_mock_wmfw_add_coeff_desc() the value stored in longstring->len
needs a cpu_to_le16() conversion.

Fixes: 5cf1b7b ("firmware: cs_dsp: Add mock wmfw file generator for KUnit testing")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202412170233.8DnsdtY6-lkp@intel.com/
Signed-off-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Link: https://patch.msgid.link/20241217105624.139479-1-rf@opensource.cirrus.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: rfvirgil

drivers/firmware/cirrus/test/cs_dsp_mock_wmfw.c

@@ -334,7 +334,7 @@ void cs_dsp_mock_wmfw_add_coeff_desc(struct cs_dsp_mock_wmfw_builder *builder,
 				  sizeof(*ple32)) / sizeof(*ple32);
 
 		longstring = (__force struct wmfw_long_string *)ple32;
-		longstring->len = description_len;
+		longstring->len = cpu_to_le16(description_len);
 		memcpy(longstring->data, def->description, description_len);
 
 		/* Round up to next __le32 multiple */