Revert 'miniz: apply CVE-2018-12913 fix from mainstream'

This reverts commit 3fd5553

Reported to cause failure in embedded file extraction in vkquake
Issue reported to mainstream at:
richgel999/miniz#329.

(cherry picked from commit 271d588)

Quake/miniz.c

@@ -649,12 +649,6 @@ tinfl_status tinfl_decompress(tinfl_decompressor *r, const mz_uint8 *pIn_buf_nex
                         bit_buf >>= code_len;
                         num_bits -= code_len;
 
-                        /* assert(sym2 != 0 && counter != 0); */
-                        if (sym2 == 0 && counter == 0)
-                        {
-                            TINFL_CR_RETURN_FOREVER(40, TINFL_STATUS_FAILED);
-                        }
-
                         pOut_buf_cur[0] = (mz_uint8)counter;
                         if (sym2 & 256)
                         {