Fix `Int` Boundary Checks

[fsagbuya]

ARTIQ Pull Request

Description of Changes

From #2320

Fix boundary check for int32 and int64.

Use <= operator to make it clear that the bounds are inclusive.

Current implementation leads to these issues (see IntBoundaryTest here):

int32:

error: cannot unify numpy.int64 with numpy.int32: 64 is incompatible with 32

int64:

error: integer literal out of range for a signed 64-bit value
-9223372036854775808
^^^^^^^^^^^^^^^^^^^^

Type of Changes

	Type
✓	:bug: Bug fix

Steps (Choose relevant, delete irrelevant before submitting)

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