powerpc/kexec_file: print error string on usable memory property update failure

Print the FDT error description along with the error message if failed
to set the "linux,drconf-usable-memory" property in the kdump kernel's
FDT.

Signed-off-by: Sourabh Jain <[email protected]>
Acked-by: Hari Bathini <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: sourabhjains

arch/powerpc/kexec/file_load_64.c

@@ -690,7 +690,8 @@ static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem)
 		ret = fdt_setprop(fdt, node, "linux,drconf-usable-memory",
 				  um_info.buf, (um_info.idx * sizeof(u64)));
 		if (ret) {
-			pr_err("Failed to update fdt with linux,drconf-usable-memory property");
+			pr_err("Failed to update fdt with linux,drconf-usable-memory property: %s",
+			       fdt_strerror(ret));
 			goto out;
 		}
 	}