DLS parser: fix wave pool size check.

Bug: 21132860.
Change-Id: I8ae872ea2cc2e8fec5fa0b7815f0b6b31ce744ff
(cherry picked from commit 2d7f8e1be2241e48458f5d3cab5e90be2b07c699)
diff --git a/arm-wt-22k/lib_src/eas_mdls.c b/arm-wt-22k/lib_src/eas_mdls.c
index e8dc463..51cce70 100644
--- a/arm-wt-22k/lib_src/eas_mdls.c
+++ b/arm-wt-22k/lib_src/eas_mdls.c
@@ -938,7 +938,7 @@
     }
 
     // limit to reasonable size
-    if (dataSize > MAX_DLS_WAVE_SIZE)
+    if (dataSize < 0 || dataSize > MAX_DLS_WAVE_SIZE)
     {
         return EAS_ERROR_SOUND_LIBRARY;
     }