video: Fix -Wcomma warnings in miniz

e.g.
SDL3/src/video/miniz.h:1058:19: warning: possible misuse of comma operator here [-Wcomma]
 1058 |       s1 += ptr[0], s2 += s1; s1 += ptr[1], s2 += s1; s1 += ptr[2], s2 += s1; s1 += ptr[3], s2 += s1;

src/video/miniz.h

@@ -1055,11 +1055,11 @@ mz_ulong mz_adler32(mz_ulong adler, const unsigned char *ptr, size_t buf_len)
   if (!ptr) return MZ_ADLER32_INIT;
   while (buf_len) {
     for (i = 0; i + 7 < block_len; i += 8, ptr += 8) {
-      s1 += ptr[0], s2 += s1; s1 += ptr[1], s2 += s1; s1 += ptr[2], s2 += s1; s1 += ptr[3], s2 += s1;
-      s1 += ptr[4], s2 += s1; s1 += ptr[5], s2 += s1; s1 += ptr[6], s2 += s1; s1 += ptr[7], s2 += s1;
+      s1 += ptr[0]; s2 += s1; s1 += ptr[1]; s2 += s1; s1 += ptr[2]; s2 += s1; s1 += ptr[3]; s2 += s1;
+      s1 += ptr[4]; s2 += s1; s1 += ptr[5]; s2 += s1; s1 += ptr[6]; s2 += s1; s1 += ptr[7]; s2 += s1;
     }
-    for ( ; i < block_len; ++i) s1 += *ptr++, s2 += s1;
-    s1 %= 65521U, s2 %= 65521U; buf_len -= block_len; block_len = 5552;
+    for ( ; i < block_len; ++i) { s1 += *ptr++; s2 += s1; }
+    s1 %= 65521U; s2 %= 65521U; buf_len -= block_len; block_len = 5552;
   }
   return (s2 << 16) + s1;
 }
@@ -2291,7 +2291,7 @@ static int tdefl_flush_block(tdefl_compressor *d, int flush)
   if ( ((use_raw_block) || ((d->m_total_lz_bytes) && ((d->m_pOutput_buf - pSaved_output_buf + 1U) >= d->m_total_lz_bytes))) &&
        ((d->m_lookahead_pos - d->m_lz_code_buf_dict_pos) <= d->m_dict_size) )
   {
-    mz_uint i; d->m_pOutput_buf = pSaved_output_buf; d->m_bit_buffer = saved_bit_buf, d->m_bits_in = saved_bits_in;
+    mz_uint i; d->m_pOutput_buf = pSaved_output_buf; d->m_bit_buffer = saved_bit_buf; d->m_bits_in = saved_bits_in;
     TDEFL_PUT_BITS(0, 2);
     if (d->m_bits_in) { TDEFL_PUT_BITS(0, 8 - d->m_bits_in); }
     for (i = 2; i; --i, d->m_total_lz_bytes ^= 0xFFFF)
@@ -2306,7 +2306,7 @@ static int tdefl_flush_block(tdefl_compressor *d, int flush)
   // Check for the extremely unlikely (if not impossible) case of the compressed block not fitting into the output buffer when using dynamic codes.
   else if (!comp_block_succeeded)
   {
-    d->m_pOutput_buf = pSaved_output_buf; d->m_bit_buffer = saved_bit_buf, d->m_bits_in = saved_bits_in;
+    d->m_pOutput_buf = pSaved_output_buf; d->m_bit_buffer = saved_bit_buf; d->m_bits_in = saved_bits_in;
     tdefl_compress_block(d, MZ_TRUE);
   }