add a + character as well to kernelVersionPattern

Signed-off-by: Logan Bond <lbond@secureworks.com>

pkg/kernelrelease/kernelrelease.go

@@ -11,7 +11,7 @@ import (
 )
 
 var (
-	kernelVersionPattern = regexp.MustCompile(`(?P<fullversion>^(?P<version>0|[1-9]\d*)\.(?P<patchlevel>0|[1-9]\d*)\.(?P<sublevel>0|[1-9]\d*))(?P<fullextraversion>[-|.](?P<extraversion>0|[1-9]\d*|\d*[a-zA-Z-~][0-9a-zA-Z-]*)(\.(0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-_]*))*)?(\+[0-9a-zA-Z-]+(\.[0-9a-zA-Z-]+)*)?$`)
+	kernelVersionPattern = regexp.MustCompile(`(?P<fullversion>^(?P<version>0|[1-9]\d*)\.(?P<patchlevel>0|[1-9]\d*)\.(?P<sublevel>0|[1-9]\d*))(?P<fullextraversion>[-|.](?P<extraversion>0|[1-9]\d*|\d*[a-zA-Z-~+][0-9a-zA-Z-~]*)(\.(0|[1-9]\d*|\d*[a-zA-Z-][0-9a-zA-Z-_]*))*)?(\+[0-9a-zA-Z-]+(\.[0-9a-zA-Z-]+)*)?$`)
 )
 
 const (