Fix incorrect usage of relative pcs.

When stepping, it's necessary to use both the unaltered relative pc
and the adjusted relative pc. If the adjusted pc is not used, the
wrong unwind information can be used.

Added new offline unit tests that take real data and verifies that it
unwinds properly.

Fix a bug in the map code that would not properly parse map data for
a 64 bit process when done in a 32 bit process.

Fix bug in eh_frame processing that didn't adjust the pc correctly.
Fix unit tests related to the pc adjustment.

Bug: 69475565

Test: Passes libbacktrace/libunwindstack unit tests.
Test: Run debuggerd -b on processes on a hikey.
Change-Id: Ic501a1c4549c5f61d2742a7105c42a960f2c892b