llvm-nm should show a symbol type of T for symbols in the (__TEXT_EXEC,__text) section.

When a the Apple link editor builds a kext bundle file type and the 
value of the -miphoneos-version-min argument is significantly current
(like 11.0) then the (__TEXT,__text) section is changed to the
(__TEXT_EXEC,__text) section.  So it would be nice for llvm-nm to
show symbols in that section with a type of T instead of the generic
type of S for some section other than text, data, etc.

rdar://36262205

llvm-svn: 323836