x86/microcode: Use the DEVICE_ATTR_RO() macro

Use DEVICE_ATTR_RO() helper instead of open-coded DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

No change in functionality.
Signed-off-by: Guangju Wang[baidu] <wgj900@163.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Borislav Petkov (AMD) <bp@alien8.de>
Link: https://lore.kernel.org/r/20230118023554.1898-1-wgj900@163.com

arch/x86/kernel/cpu/microcode/core.c

@@ -507,7 +507,7 @@ static ssize_t version_show(struct device *dev,
 	return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
 }
 
-static ssize_t pf_show(struct device *dev,
+static ssize_t processor_flags_show(struct device *dev,
 			struct device_attribute *attr, char *buf)
 {
 	struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
@@ -515,8 +515,8 @@ static ssize_t pf_show(struct device *dev,
 	return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
 }
 
-static DEVICE_ATTR(version, 0444, version_show, NULL);
-static DEVICE_ATTR(processor_flags, 0444, pf_show, NULL);
+static DEVICE_ATTR_RO(version);
+static DEVICE_ATTR_RO(processor_flags);
 
 static struct attribute *mc_default_attrs[] = {
 	&dev_attr_version.attr,