cxl: downgrade a warning message to debug level in cxl_probe_component_regs()

In cxl_probe_component_regs() the error message "Couldn't locate the
CXL.cache and CXL.mem capability array header." is potentially a false
positive error condition.

Downgrade the message from error level to debug level by using dev_dbg()
to print the message, and the end users won't worry about the message
anymore.

[djbw/iweiny: Fix up changelog]

Reported-by: Kelvin Shieh <kshieh@lenovo.com>
Signed-off-by: Coly Li <colyli@suse.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jonathan Cameron <Jonathan.Cameron@Huawei.com>
Cc: Alison Schofield <alison.schofield@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Link: https://patch.msgid.link/20241021050443.318712-1-colyli@suse.de
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>

Author: Coly Li

drivers/cxl/core/regs.c

@@ -52,7 +52,7 @@ void cxl_probe_component_regs(struct device *dev, void __iomem *base,
 	cap_array = readl(base + CXL_CM_CAP_HDR_OFFSET);
 
 	if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) {
-		dev_err(dev,
+		dev_dbg(dev,
 			"Couldn't locate the CXL.cache and CXL.mem capability array header.\n");
 		return;
 	}