dev: Add dev_vprintk_emit and dev_printk_emit

Add utility functions to consolidate the use of
create_syslog_header and vprintk_emit.

This allows conversion of logging functions that
call create_syslog_header and then call vprintk_emit
or printk_emit to the dev_ equivalents.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Jim Cromie <jim.cromie@gmail.com>
Acked-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/base/core.c b/drivers/base/core.c
index d325b9d..dff94c8 100644
--- a/drivers/base/core.c
+++ b/drivers/base/core.c
@@ -1913,6 +1913,33 @@
 }
 EXPORT_SYMBOL(create_syslog_header);
 
+int dev_vprintk_emit(int level, const struct device *dev,
+		     const char *fmt, va_list args)
+{
+	char hdr[128];
+	size_t hdrlen;
+
+	hdrlen = create_syslog_header(dev, hdr, sizeof(hdr));
+
+	return vprintk_emit(0, level, hdrlen ? hdr : NULL, hdrlen, fmt, args);
+}
+EXPORT_SYMBOL(dev_vprintk_emit);
+
+int dev_printk_emit(int level, const struct device *dev, const char *fmt, ...)
+{
+	va_list args;
+	int r;
+
+	va_start(args, fmt);
+
+	r = dev_vprintk_emit(level, dev, fmt, args);
+
+	va_end(args);
+
+	return r;
+}
+EXPORT_SYMBOL(dev_printk_emit);
+
 static int __dev_printk(const char *level, const struct device *dev,
 			struct va_format *vaf)
 {