ARM: Be consistent about the condition codes used with CompareObjectType

ARM: Be consistent about the condition codes used with CompareObjectType

Now the signed comparison condition codes are always used with CompareObjectType. The type is only a byte and ldrb will do sign extension, so signed and unsigned comparison will give the same result. Signed condition codes are easier to read.

R=erik.corry@gmail.com

BUG=none
TEST=none

Review URL: http://codereview.chromium.org//7104019

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@8134 ce2b1a6d-e550-0410-aec6-3dcde31c8c00