Remove excess checks before free()

References:
- https://pubs.opengroup.org/onlinepubs/009695399/functions/free.html
- https://stackoverflow.com/a/18775633

compat/ioapi.c

@@ -211,7 +211,6 @@ void mz_stream_ioapi_delete(void **stream) {
     if (!stream)
         return;
     ioapi = (mz_stream_ioapi *)*stream;
-    if (ioapi)
     free(ioapi);
     *stream = NULL;
 }

mz_strm.c

@@ -537,7 +537,6 @@ void mz_stream_raw_delete(void **stream) {
     if (!stream)
         return;
     raw = (mz_stream_raw *)*stream;
-    if (raw)
     free(raw);
     *stream = NULL;
 }

mz_strm_buf.c

@@ -372,7 +372,6 @@ void mz_stream_buffered_delete(void **stream) {
     if (!stream)
         return;
     buffered = (mz_stream_buffered *)*stream;
-    if (buffered)
     free(buffered);
     *stream = NULL;
 }

mz_strm_bzip.c

@@ -336,7 +336,6 @@ void mz_stream_bzip_delete(void **stream) {
     if (!stream)
         return;
     bzip = (mz_stream_bzip *)*stream;
-    if (bzip)
     free(bzip);
     *stream = NULL;
 }

mz_strm_lzma.c

@@ -443,7 +443,6 @@ void mz_stream_lzma_delete(void **stream) {
     if (!stream)
         return;
     lzma = (mz_stream_lzma *)*stream;
-    if (lzma)
     free(lzma);
     *stream = NULL;
 }

mz_strm_os_posix.c

@@ -186,7 +186,6 @@ void mz_stream_os_delete(void **stream) {
     if (!stream)
         return;
     posix = (mz_stream_posix *)*stream;
-    if (posix)
     free(posix);
     *stream = NULL;
 }

mz_strm_pkcrypt.c

@@ -315,7 +315,6 @@ void mz_stream_pkcrypt_delete(void **stream) {
     if (!stream)
         return;
     pkcrypt = (mz_stream_pkcrypt *)*stream;
-    if (pkcrypt)
     free(pkcrypt);
     *stream = NULL;
 }

mz_strm_split.c

@@ -404,11 +404,8 @@ void mz_stream_split_delete(void **stream) {
         return;
     split = (mz_stream_split *)*stream;
     if (split) {
-        if (split->path_cd)
         free(split->path_cd);
-        if (split->path_disk)
         free(split->path_disk);
-
         free(split);
     }
     *stream = NULL;

mz_strm_zlib.c

@@ -369,7 +369,6 @@ void mz_stream_zlib_delete(void **stream) {
     if (!stream)
         return;
     zlib = (mz_stream_zlib *)*stream;
-    if (zlib)
     free(zlib);
     *stream = NULL;
 }

mz_strm_zstd.c

@@ -327,7 +327,6 @@ void mz_stream_zstd_delete(void **stream) {
     if (!stream)
         return;
     zstd = (mz_stream_zstd *)*stream;
-    if (zstd)
     free(zstd);
     *stream = NULL;
 }

mz_zip.c

@@ -1416,9 +1416,7 @@ void mz_zip_delete(void **handle) {
     if (!handle)
         return;
     zip = (mz_zip *)*handle;
-    if (zip) {
     free(zip);
-    }
     *handle = NULL;
 }
 
@@ -1560,7 +1558,6 @@ int32_t mz_zip_set_comment(void *handle, const char *comment) {
     int32_t comment_size = 0;
     if (!zip || !comment)
         return MZ_PARAM_ERROR;
-    if (zip->comment)
     free(zip->comment);
     comment_size = (int32_t)strlen(comment);
     if (comment_size > UINT16_MAX)