Fix a bunch of spelling mistakes :\

src/assembler-arm.cc

Index: src/assembler-arm.cc
diff --git a/src/assembler-arm.cc b/src/assembler-arm.cc
index 4e3ae1afc0a509375769046f4929125823249301..f7725f669bb01bae7442b3bcf7538859aadcb201 100644
--- a/src/assembler-arm.cc
+++ b/src/assembler-arm.cc
@@ -1331,7 +1331,7 @@ void Assembler::WriteRecordedPositions() {
   }
 
   // Write the position if it is different from what was written last time and
-  // also diferent from the written statement position.
+  // also different from the written statement position.
   if (current_position_ != written_position_ &&
       current_position_ != written_statement_position_) {
     CheckBuffer();