Apply suggestions from code review for flipped conditions.

Co-Authored-By: EraYaN <EraYaN@users.noreply.github.com>

MediaBrowser.MediaEncoding/Configuration/EncodingConfigurationFactory.cs

@@ -46,7 +46,7 @@ namespace MediaBrowser.MediaEncoding.Configuration
                 && !string.Equals(oldEncodingConfig.TranscodingTempPath ?? string.Empty, newPath))
             {
                 // Validate
-                if (Directory.Exists(newPath))
+                if (!Directory.Exists(newPath))
                 {
                     throw new FileNotFoundException(string.Format("{0} does not exist.", newPath));
                 }

MediaBrowser.MediaEncoding/Encoder/MediaEncoder.cs

@@ -214,7 +214,7 @@ namespace MediaBrowser.MediaEncoding.Encoder
                     throw new ArgumentNullException(nameof(path));
                 }
 
-                if (!File.Exists(path) && Directory.Exists(path))
+                if (!File.Exists(path) && !Directory.Exists(path))
                 {
                     throw new ResourceNotFoundException();
                 }

MediaBrowser.Providers/TV/MissingEpisodeProvider.cs

@@ -58,7 +58,7 @@ namespace MediaBrowser.Providers.TV
             }
 
             // Check this in order to avoid logging an exception due to directory not existing
-            if (Directory.Exists(seriesDataPath))
+            if (!Directory.Exists(seriesDataPath))
             {
                 return false;
             }