[clang-tidy] Make `P +- BS / sizeof(*P)` opt-outable in `bugprone-sizeof-expression` (#111178)

In some cases and for projects that deal with a lot of low-level buffers, a
pattern often emerges that

[clang-tidy] Make `P +- BS / sizeof(*P)` opt-outable in `bugprone-sizeof-expression` (#111178)

In some cases and for projects that deal with a lot of low-level buffers, a
pattern often emerges that an array and its full size, not in the number of
"elements" but in "bytes", are known with no syntax-level connection between
the two values.
To access the array elements, the pointer arithmetic involved will have
to divide 'SizeInBytes' (a numeric value) with `sizeof(*Buffer)`.
Since the previous patch introduced this new warning, potential
false-positives were triggered from `bugprone-sizeof-expression`, as `sizeof`
appeared in pointer arithmetic where integers are scaled.

This patch adds a new check option, `WarnOnOffsetDividedBySizeOf`, which allows
users to opt out of warning about the division case.
In arbitrary projects, it might still be worthwhile to get these warnings until
an opt-out from the detection of scaling issues, especially if a project
might not be using low-level buffers intensively.

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[clang-tidy] Extend `bugprone-sizeof-expression` with matching `P +- sizeof(T)` and `P +- N */ sizeof(T)` cases, add `cert-arr39-c` alias (#106061)

Improved `bugprone-sizeof-expression` check to fin

[clang-tidy] Extend `bugprone-sizeof-expression` with matching `P +- sizeof(T)` and `P +- N */ sizeof(T)` cases, add `cert-arr39-c` alias (#106061)

Improved `bugprone-sizeof-expression` check to find suspicious pointer
arithmetic calculations where the pointer is offset by an `alignof()`,
`offsetof()`, or `sizeof()` expression.

Pointer arithmetic expressions implicitly scale the offset added to or
subtracted from the address by the size of the pointee type. Using an
offset expression that is already scaled by the size of the underlying
type effectively results in a squared offset, which is likely an invalid
pointer that points beyond the end of the intended array.

```c
void printEveryEvenIndexElement(int *Array, size_t N) {
int *P = Array;
while (P <= Array + N * sizeof(int)) { // Suspicious pointer arithmetics using sizeof()!
printf("%d ", *P);

P += 2 * sizeof(int); // Suspicious pointer arithmetics using sizeof()!
}
}
```

---------

Co-authored-by: Whisperity <whisperity@gmail.com>

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