fix  warning: struct argument contains uninitialized data

This fixes the warning warning: Passed-by-value struct argument contains
uninitialized data (e.g., field: 'command') [clang-analyzer-core.CallAndMessage]

Bug: None
Test: The warning is gone.
Change-Id: I3e06ff484bdec995c5125433acb5c3f14dc29dd9
diff --git a/media/mtp/MtpServer.cpp b/media/mtp/MtpServer.cpp
index 753d833..5a1d6dc 100644
--- a/media/mtp/MtpServer.cpp
+++ b/media/mtp/MtpServer.cpp
@@ -1060,6 +1060,9 @@
                 mfr.length = mSendObjectFileSize - initialData;
             }
 
+            mfr.command = 0;
+            mfr.transaction_id = 0;
+
             // transfer the file
             ret = sHandle->receiveFile(mfr);
             if ((ret < 0) && (errno == ECANCELED)) {
@@ -1257,6 +1260,8 @@
             mfr.fd = edit->mFD;
             mfr.offset = offset;
             mfr.length = length;
+            mfr.command = 0;
+            mfr.transaction_id = 0;
 
             // transfer the file
             ret = sHandle->receiveFile(mfr);