MIPS: Unbreak gn build, missing source files for MIPS tf.

TEST=
BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/654583002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24564 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

BUILD.gn

@@ -1127,6 +1127,10 @@ source_set("v8_base") {
       "src/mips/regexp-macro-assembler-mips.cc",
       "src/mips/regexp-macro-assembler-mips.h",
       "src/mips/simulator-mips.cc",
+      "src/compiler/mips/code-generator-mips.cc",
+      "src/compiler/mips/instruction-codes-mips.h",
+      "src/compiler/mips/instruction-selector-mips.cc",
+      "src/compiler/mips/linkage-mips.cc",
       "src/ic/mips/access-compiler-mips.cc",
       "src/ic/mips/handler-compiler-mips.cc",
       "src/ic/mips/ic-mips.cc",