riscv: selftests: Remove mmap hint address checks

The mmap behavior that restricts the addresses returned by mmap caused
unexpected behavior, so get rid of the test cases that check that
behavior.

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Fixes: 73d05262 ("selftests: riscv: Generalize mm selftests")
Link: https://lore.kernel.org/r/20240826-riscv_mmap-v1-2-cd8962afe47f@rivosinc.com


Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>