MIPS: Fix label position types in binding code.

src/mips64/assembler-mips64.h

Index: src/mips64/assembler-mips64.h
diff --git a/src/mips64/assembler-mips64.h b/src/mips64/assembler-mips64.h
index 5ad98f6cd88135a43c282b42651f79fd184b26ef..a550ef2c8b575b769cf7b789b830455dfefa5b60 100644
--- a/src/mips64/assembler-mips64.h
+++ b/src/mips64/assembler-mips64.h
@@ -1168,10 +1168,10 @@ class Assembler : public AssemblerBase {
   int64_t buffer_space() const { return reloc_info_writer.pos() - pc_; }
 
   // Decode branch instruction at pos and return branch target pos.
-  int64_t target_at(int64_t pos, bool is_internal);
+  int target_at(int pos, bool is_internal);
 
   // Patch branch instruction at pos to branch to given branch target pos.
-  void target_at_put(int64_t pos, int64_t target_pos, bool is_internal);
+  void target_at_put(int pos, int target_pos, bool is_internal);
 
   // Say if we need to relocate with this mode.
   bool MustUseReg(RelocInfo::Mode rmode);