Audio VTS: Fix MMAP tests

Ensure stream test runs for output MMAP profiles.

Enhance checks for MMAP buffer size.

Bug: 144575694
Test: atest VtsHalAudioV6_0TargetTest
Change-Id: I93e66b12c93c466d661e65c4dbbb5deb32772848
diff --git a/audio/6.0/IStream.hal b/audio/6.0/IStream.hal
index 451e116..b48a05d 100644
--- a/audio/6.0/IStream.hal
+++ b/audio/6.0/IStream.hal
@@ -277,7 +277,7 @@
      * @return retval OK in case the success.
      *                NOT_SUPPORTED on non mmap mode streams
      *                NOT_INITIALIZED in case of memory allocation error
-     *                INVALID_ARGUMENTS if the requested buffer size is too large
+     *                INVALID_ARGUMENTS if the requested buffer size is invalid
      *                INVALID_STATE if called out of sequence
      * @return info    a MmapBufferInfo struct containing information on the MMMAP buffer created.
      */