try removing attribute((aligned(16))

CQ_EXTRA_TRYBOTS=client.skia:Test-iOS-Clang-iPad4-GPU-SGX554-Arm7-Release-Trybot

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1618873005

TBR=reed@google.com

Review URL: https://codereview.chromium.org/1618873005
diff --git a/include/core/SkColor.h b/include/core/SkColor.h
index 7794638..f18fb7e 100644
--- a/include/core/SkColor.h
+++ b/include/core/SkColor.h
@@ -165,7 +165,7 @@
 /*
  *  The float values are 0...1 premultiplied
  */
-struct SK_ATTRIBUTE(aligned(16)) SkPM4f {
+struct SkPM4f {
     float fVec[4];
 
     float a() const { return fVec[SK_A32_SHIFT/8]; }