Add MIPS SIMD Arch (MSA) build flags for GYP/GN builds

build/config/compiler/BUILD.gn

Index: build/config/compiler/BUILD.gn
diff --git a/build/config/compiler/BUILD.gn b/build/config/compiler/BUILD.gn
index 30d801789d8a36aeab008f75aeedea2afacebe79..a31b34e5b83d3b0de77857c6fb7b12cbc750aa8c 100644
--- a/build/config/compiler/BUILD.gn
+++ b/build/config/compiler/BUILD.gn
@@ -568,6 +568,14 @@ config("compiler_cpu_abi") {
             ]
           }
         }
+        if (mips_use_msa == true) {
+          cflags += [
+            "-mmsa",
+            "-mfp64",
+            "-msched-weight",
+            "-mload-store-pairs",
+          ]
+        }
       } else if (mips_arch_variant == "r2") {
         if (is_clang) {
           if (is_android) {
@@ -644,6 +652,14 @@ config("compiler_cpu_abi") {
           ]
           ldflags += [ "-mips64r6" ]
         }
+        if (mips_use_msa == true) {
+          cflags += [
+            "-mmsa",
+            "-mfp64",
+            "-msched-weight",
+            "-mload-store-pairs",
+          ]
+        }
       } else if (mips_arch_variant == "r2") {
         cflags += [
           "-mips64r2",