[PATCH v2] arm: Don't require a runtime check function for targets with unconditional NEON

If the compiler is set up to unconditionally use NEON instructions
anywhere, we don't need any function for runtime detection.

This fixes building for non-Linux OSes with unconditionally
available NEON, such as iOS and Windows.
---
This is the minimal first step that fixes the issues I've seen.
---
 pngpriv.h | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pngpriv.h b/pngpriv.h
index 2e426cf47..b07726d4b 100644
--- a/pngpriv.h
+++ b/pngpriv.h
@@ -130,6 +130,7 @@
 #  if (defined(__ARM_NEON__) || defined(__ARM_NEON)) && \
    defined(PNG_ALIGNED_MEMORY_SUPPORTED)
 #     define PNG_ARM_NEON_OPT 2
+#     undef PNG_ARM_NEON_CHECK_SUPPORTED
 #  else
 #     define PNG_ARM_NEON_OPT 0
 #  endif
-- 
2.37.0 (Apple Git-136)