Replace NEON assembly memset16 and memset32 with intrinsic versions.

src/opts/SkUtils_opts_arm.cpp

 /*
  * Copyright 2014 ARM Ltd.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkUtils.h"
 #include "SkUtilsArm.h"
 
-extern "C" void memset16_neon(uint16_t dst[], uint16_t value, int count);
-extern "C" void memset32_neon(uint32_t dst[], uint32_t value, int count);
+void sk_memset16_neon(uint16_t dst[], uint16_t value, int count);
+void sk_memset32_neon(uint32_t dst[], uint32_t value, int count);
 
 SkMemset16Proc SkMemset16GetPlatformProc() {
 #if SK_ARM_NEON_IS_ALWAYS
-    return memset16_neon;
+    return sk_memset16_neon;
 #elif SK_ARM_NEON_IS_DYNAMIC
-    return sk_cpu_arm_has_neon() ? memset16_neon : nullptr;
+    return sk_cpu_arm_has_neon() ? sk_memset16_neon : nullptr;
 #else
     return nullptr;
 #endif
 }
 
 SkMemset32Proc SkMemset32GetPlatformProc() {
 #if SK_ARM_NEON_IS_ALWAYS
-    return memset32_neon;
+    return sk_memset32_neon;
 #elif SK_ARM_NEON_IS_DYNAMIC
-    return sk_cpu_arm_has_neon() ? memset32_neon : nullptr;
+    return sk_cpu_arm_has_neon() ? sk_memset32_neon : nullptr;
 #else
     return nullptr;
 #endif
 }
 
 SkMemcpy32Proc SkMemcpy32GetPlatformProc() {
     return NULL;
 }