Add `c_devloc` as intrinsic and inline it during lowering. `c_devloc` is
used in CUDA Fortran to get the address of device variables.
For the moment, we borrow almost all semantic checks from `c_loc` except
for the pointer or target restriction. The specifications of `c_devloc`
are are pretty vague and we will relax/enforce the restrictions based on
library and apps usage comparing them to the reference compiler.