Reland "[lldb] Remove non address bits when looking up memory regions"

(cherry picked from 2937b282)

This reverts commit 0df52296.

Additional checks are added to fix the detection of the last memory region
in GetMemoryRegions or repeating the "memory region" command when the
target has non-address bits.

Normally you keep reading from address 0, looking up each region's end
address until you get LLDB_INVALID_ADDR as the region end address.
(0xffffffffffffffff)

This is what the remote will return once you go beyond the last mapped region:
[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0001000000000000-0xffffffffffffffff) ---

Problem is that when we "fix" the lookup address, we remove some bits
from it. On an AArch64 system we have 48 bit virtual addresses, so when
we fix the end address of the [stack] region the result is 0.
So we loop back to the start.

[0x0000fffffffdf000-0x0001000000000000) rw- [stack]
[0x0000000000000000-0x000...