Fix potential index out of range error

I had some extra spaces and junk in my ssh config and it was causing
this part of the code to fail with an out of range error.

parser.go

@@ -107,19 +107,17 @@ func (p *sshParser) parseKV() sshParserStateFn {
 	}
 	if strings.ToLower(key.val) == "host" {
 		strPatterns := strings.Split(val.val, " ")
+		patterns := make([]*Pattern, 0)
 		for i := range strPatterns {
 			if strPatterns[i] == "" {
-				strPatterns = append(strPatterns[:i], strPatterns[i+1:]...)
+				continue
 			}
-		}
-		patterns := make([]*Pattern, len(strPatterns))
-		for i := range strPatterns {
 			pat, err := NewPattern(strPatterns[i])
 			if err != nil {
 				p.raiseErrorf(val, "Invalid host pattern: %v", err)
 				return nil
 			}
-			patterns[i] = pat
+			patterns = append(patterns, pat)
 		}
 		p.config.Hosts = append(p.config.Hosts, &Host{
 			Patterns:   patterns,