[flang] Lower TRANSPOSE without using runtime.

Calling runtime TRANSPOSE requires a temporary array for the result,
and, sometimes, a temporary array for the argument. Lowering it inline
should provide faster code.

I added -opt-transpose control just for debugging purposes temporary.
I am going to make driver changes that will disable inline lowering
for -O0. For the time being I would like to enable it by default
to expose the code to more tests.

Differential Revision: https://reviews.llvm.org/D129497