tools/testing/cxl: Remove cxl_test module math loading message

Commit "tools/testing/cxl: Add XOR Math support to cxl_test" added
a module parameter to cxl_test for the interleave_arithmetic option.

In doing so, it also added this dev_dbg() message describing which
option cxl_test used during load:
"[  111.743246] (NULL device *): cxl_test loading modulo math option"
That "(NULL device *)" has raised needless user concern.

Remove the dev_dbg() message and make the module_param readable via
sysfs for users that need to know which math option is active.
Suggested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Link: https://lore.kernel.org/r/20230126170555.701240-1-alison.schofield@intel.comSigned-off-by: Alison Schofield <alison.schofield@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

tools/testing/cxl/test/cxl.c

@@ -1143,11 +1143,9 @@ static __init int cxl_test_init(void)
 	if (interleave_arithmetic == 1) {
 		cfmws_start = CFMWS_XOR_ARRAY_START;
 		cfmws_end = CFMWS_XOR_ARRAY_END;
-		dev_dbg(NULL, "cxl_test loading xor math option\n");
 	} else {
 		cfmws_start = CFMWS_MOD_ARRAY_START;
 		cfmws_end = CFMWS_MOD_ARRAY_END;
-		dev_dbg(NULL, "cxl_test loading modulo math option\n");
 	}
 
 	rc = populate_cedt();
@@ -1334,7 +1332,7 @@ static __exit void cxl_test_exit(void)
 	unregister_cxl_mock_ops(&cxl_mock_ops);
 }
 
-module_param(interleave_arithmetic, int, 0000);
+module_param(interleave_arithmetic, int, 0444);
 MODULE_PARM_DESC(interleave_arithmetic, "Modulo:0, XOR:1");
 module_init(cxl_test_init);
 module_exit(cxl_test_exit);