remoteproc: k3: Fix NULL vs IS_ERR() bug in k3_reserved_mem_init()

commit 5b1f4b5 upstream.

The devm_ioremap_resource_wc() function never returns NULL, it returns
error pointers.  Update the error checking to match.

Fixes: 67a7bc7 ("remoteproc: Use of_reserved_mem_region_* functions for "memory-region"")
Signed-off-by: Chen Ni <nichen@iscas.ac.cn>
Reviewed-by: Peng Fan <peng.fan@nxp.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20260227092110.4044313-1-nichen@iscas.ac.cn
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Chen Ni

drivers/remoteproc/ti_k3_common.c

@@ -513,7 +513,7 @@ int k3_reserved_mem_init(struct k3_rproc *kproc)
 		kproc->rmem[i].dev_addr = (u32)res.start;
 		kproc->rmem[i].size = resource_size(&res);
 		kproc->rmem[i].cpu_addr = devm_ioremap_resource_wc(dev, &res);
-		if (!kproc->rmem[i].cpu_addr) {
+		if (IS_ERR(kproc->rmem[i].cpu_addr)) {
 			dev_err(dev, "failed to map reserved memory#%d at %pR\n",
 				i + 1, &res);
 			return -ENOMEM;