A ULP program is built against ulp_riscv, lp_core or ulp_fsm, each stating its
own sources, dependencies and memory layout. Sources shared with the driver
stay in components/ulp.
This commit refactors the ulp component.
Files are now divided based on type of ulp, viz., fsm or risc-v.
Files common to both are maintained in the ulp_common folder.
This commit also adds menuconfig options for ULP within the ulp
component instead of presenting target specific configuations for ulp.
