removed limit ZSTD_TARGETLENGTH_MAX

this makes it possible to specify extremely large negative compression levels,
achieving the side effect as "no compression".

It will also be possible to define larger targetlength for ultra compression mode.

There is no adverse side effect due to removing this limit.

programs/zstdcli.c

@@ -388,7 +388,7 @@ int main(int argCount, const char* argv[])
     zstd_operation_mode operation = zom_compress;
     ZSTD_compressionParameters compressionParams;
     int cLevel = ZSTDCLI_CLEVEL_DEFAULT;
-    int cLevelLast = -10000;
+    int cLevelLast = -1000000000;
     unsigned recursive = 0;
     unsigned memLimit = 0;
     const char** filenameTable = (const char**)malloc(argCount * sizeof(const char*));   /* argCount >= 1 */