Surpress warnings in minzip/Zip.c

bootable/recovery/minzip/Zip.c:514:5: warning: Value stored to 'compRemaining' is never read
    compRemaining = pEntry->compLen;
        ^               ~~~~~~~~~~~~~~~
  bootable/recovery/minzip/Zip.c:778:9: warning: Null pointer argument in call to memory copy function
    memcpy(p, helper->targetDir, helper->targetDirLen);
         ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Bug: 27229894
Change-Id: I0482bac3a4fcddc191783d1e5b5a83cf29fa4e85

minzip/Zip.c

@@ -509,9 +509,6 @@ static bool processDeflatedEntry(const ZipArchive *pArchive,
     unsigned char procBuf[32 * 1024];
     z_stream zstream;
     int zerr;
-    long compRemaining;
-
-    compRemaining = pEntry->compLen;
 
     /*
      * Initialize the zlib stream.
@@ -759,7 +756,7 @@ static const char *targetEntryPath(MzPathHelper *helper, ZipEntry *pEntry)
      */
     needLen = helper->targetDirLen + 1 +
             pEntry->fileNameLen - helper->zipDirLen + 1;
-    if (needLen > helper->bufLen) {
+    if (firstTime || needLen > helper->bufLen) {
         char *newBuf;
 
         needLen *= 2;