gsm0503_coding: Fix misleading comment UL vs DL

Change-Id: I563c60271e218f9953e26f9bf0304d442c6acd43
diff --git a/src/coding/gsm0503_coding.c b/src/coding/gsm0503_coding.c
index 8480240..9449f4b 100644
--- a/src/coding/gsm0503_coding.c
+++ b/src/coding/gsm0503_coding.c
@@ -1168,7 +1168,7 @@
 }
 
 /*
- * EGPRS PDTCH UL block encoding
+ * EGPRS PDTCH DL block encoding
  */
 static int egprs_type3_map(ubit_t *bursts, const ubit_t *hc, const ubit_t *dc, int usf)
 {