Fix memleak in CapturePix (#1762)

Source/capture.cpp

@@ -116,16 +116,15 @@ static BYTE *CaptureEnc(BYTE *src, BYTE *dst, int width)
 static bool CapturePix(const CelOutputBuffer &buf, std::ofstream *out)
 {
 	int width = buf.w();
-	BYTE *pBuffer = (BYTE *)DiabloAllocPtr(2 * width);
+	auto pBuffer = std::make_unique<BYTE[]>(2 * width);
 	BYTE *pixels = buf.begin();
 	for (int height = buf.h(); height > 0; height--) {
-		const BYTE *pBufferEnd = CaptureEnc(pixels, pBuffer, width);
+		const BYTE *pBufferEnd = CaptureEnc(pixels, pBuffer.get(), width);
 		pixels += buf.pitch();
-		out->write(reinterpret_cast<const char *>(pBuffer), pBufferEnd - pBuffer);
+		out->write(reinterpret_cast<const char *>(pBuffer.get()), pBufferEnd - pBuffer.get());
 		if (out->fail())
 			return false;
 	}
-	mem_free_dbg(pBuffer);
 	return true;
 }