Revert "[mips] Disable compact branch generation"

With the latest Clang we do not have issue with beqc instruction,
so allow generation of compact branches for mips.

This reverts commit 3d6a38d60154f09933c6c32cb09e1f2fa142812d.

Change-Id: I6dbb5d1fce08bd714cc9a0318d50de5765cff038
diff --git a/cc/config/mips64_device.go b/cc/config/mips64_device.go
index 23d5560..3a49e7b 100644
--- a/cc/config/mips64_device.go
+++ b/cc/config/mips64_device.go
@@ -82,9 +82,6 @@
 		"mips64r6": []string{
 			"-mips64r6",
 			"-msynci",
-
-			// revert once clang picks up r278824
-			"-mcompact-branches=never",
 		},
 	}
 )
diff --git a/cc/config/mips_device.go b/cc/config/mips_device.go
index ec8f133..c135029 100644
--- a/cc/config/mips_device.go
+++ b/cc/config/mips_device.go
@@ -113,9 +113,6 @@
 			"-mfp64",
 			"-mno-odd-spreg",
 			"-msynci",
-
-			// revert once clang picks up r278824
-			"-mcompact-branches=never",
 		},
 	}
 )