Revert "Avoid assertion in opj_j2k_merge_ppt() in case premature EOC is encountered in opj_j2k_read_tile_header(). Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=2785. Credit to OSS Fuzz" (fixes #1120)

This reverts commit 9906fbf.
which broke decoding of images where TNsot == 0

Author: rouault

src/lib/openjp2/j2k.c

@@ -8845,7 +8845,10 @@ OPJ_BOOL opj_j2k_read_tile_header(opj_j2k_t * p_j2k,
 
     /* Current marker is the EOC marker ?*/
     if (l_current_marker == J2K_MS_EOC) {
-        p_j2k->m_specific_param.m_decoder.m_state = J2K_STATE_EOC;
+        if (p_j2k->m_specific_param.m_decoder.m_state != J2K_STATE_EOC) {
+            p_j2k->m_current_tile_number = 0;
+            p_j2k->m_specific_param.m_decoder.m_state = J2K_STATE_EOC;
+        }
     }
 
     /* FIXME DOC ???*/