SkPngFilters: guard with libpng >= 1.5.7

The read_filter array was added in libpng-1.5.7.
No point to these filter methods if we can't plug them into libpng.

TBR=msarett@google.com
NOTRY=true
NOPRESUBMIT=true

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1640933004

Review URL: https://codereview.chromium.org/1640933004

src/codec/SkPngCodec.cpp

@@ -17,7 +17,8 @@
 #include "SkSwizzler.h"
 #include "SkTemplates.h"
 
-#if defined(__SSE2__)
+// png_struct::read_filter[] was added in libpng 1.5.7.
+#if defined(__SSE2__) && PNG_LIBPNG_VER >= 10507
     #include "pngstruct.h"
 
     extern "C" void sk_png_init_filter_functions_sse2(png_structp png, unsigned int bpp) {