ANDROID: Revert "arm: move ELF_ET_DYN_BASE to 4MB"

This ARM mmap change breaks AddressSanitizer:

Shadow memory range interleaves with an existing memory mapping. ASan cannot proceed correctly. ABORTING.

Revert it until ASAN runtime library is updated to handle it.

Bug: 67425063

This reverts commit d2471b5e84f32de4e09b58f5436a4ce3ee935e32.

Signed-off-by: Evgenii Stepanov <eugenis@google.com>