x86/kexec: use pr_err() instead of kexec_dprintk() when an error occurs

When detecting an error, the current code uses kexec_dprintk() to output
log message. This is not quite appropriate as kexec_dprintk() is mainly
used for outputting debugging messages, rather than error messages.

Replace kexec_dprintk() with pr_err(). This also makes the output method
for this error log align with the output method for other error logs in
this function.

Additionally, the last return statement in set_page_address() is
unnecessary, remove it.

Link: https://lkml.kernel.org/r/[e-mail]
Signed-off-by: Yuntao Wang <[e-mail]>
Cc: Baoquan He <[e-mail]>
Cc: Borislav Petkov (AMD) <[e-mail]>
Cc: Dave Hansen <[e-mail]>
Cc: "Eric W. Biederman" <[e-mail]>
Cc: "H. Peter Anvin" <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Jonathan Corbet <[e-mail]>
Cc: Thomas Gleixner <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>

arch/x86/kernel/kexec-bzimage64.c

···
 	 * command line. Make sure it does not overflow
 	 */
 	if (cmdline_len + MAX_ELFCOREHDR_STR_LEN > header->cmdline_size) {
-		kexec_dprintk("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
+		pr_err("Appending elfcorehdr=<addr> to command line exceeds maximum allowed length\n");
 		return ERR_PTR(-EINVAL);
 	}
 

mm/highmem.c

···
 		}
 		spin_unlock_irqrestore(&pas->lock, flags);
 	}
-
-	return;
 }
 
 void __init page_address_init(void)