Compile BoringSSL for arm64 iOS

BUG=338886

Review URL: https://codereview.chromium.org/1064693002

Cr-Commit-Position: refs/heads/master@{#324132}

third_party/boringssl/BUILD.gn

@@ -90,9 +90,9 @@ component("boringssl") {
     } else {
       defines += [ "OPENSSL_NO_ASM" ]
     }
-  } else if (current_cpu == "arm") {
+  } else if (current_cpu == "arm" && (is_linux || is_android)) {
     sources += gypi_values.boringssl_linux_arm_sources
-  } else if (current_cpu == "arm64") {
+  } else if (current_cpu == "arm64" && (is_linux || is_android)) {
     sources += gypi_values.boringssl_linux_aarch64_sources
   } else {
     defines += [ "OPENSSL_NO_ASM" ]

third_party/boringssl/boringssl.gyp

@@ -27,10 +27,22 @@
           ],
         }],
         ['target_arch == "arm"', {
-          'sources': [ '<@(boringssl_linux_arm_sources)' ],
+          'conditions': [
+            ['OS == "linux" or OS == "android"', {
+              'sources': [ '<@(boringssl_linux_arm_sources)' ],
+            }, {
+              'defines': [ 'OPENSSL_NO_ASM' ],
+            }],
+          ],
         }],
         ['target_arch == "arm64"', {
-          'sources': [ '<@(boringssl_linux_aarch64_sources)' ],
+          'conditions': [
+            ['OS == "linux" or OS == "android"', {
+              'sources': [ '<@(boringssl_linux_aarch64_sources)' ],
+            }, {
+              'defines': [ 'OPENSSL_NO_ASM' ],
+            }],
+          ],
         }],
         ['target_arch == "ia32"', {
           'conditions': [