tests: Unit tests for erase function selection algo

The test checks that algorithm for erase functions selection
works and there are no regressions.

Specifically, test contains a number of test cases (14 at the
time of writing, but more can be added). Each case initialises a
given initial state of the memory for the mock chip, and layout
regions on the chip, and then performs erase and write operations.
At the end of operation, test asserts the state of mock chip memory
is as expected, i.e. properly erased and written.
Also test asserts operation returned 0.

TODO to be added soon: assert that erase blocks are invoked in
expected order. This part tests there are no regressions to the
algorithm.

Change-Id: I8f3fdefb76e71f6f8dc295d9dead5f38642aace7
Signed-off-by: Anastasia Klimchuk <aklm@chromium.org>
---
A tests/erase_func_algo.c
M tests/meson.build
M tests/tests.c
M tests/tests.h
4 files changed, 564 insertions(+), 0 deletions(-)