[cl.array] Prefer input arrays' constructor instead of cla.Array to instantiate the output

[kaushikcfd]

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• Version bump because of the following incoherence with numpy:

>>> import numpy as np
>>> np.hstack([])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "<__array_function__ internals>", line 180, in hstack
  File "/home/kgk2/projects/ceesd/miniforge3/envs/ceesd/lib/python3.8/site-packages/numpy/core/shape_base.py", line 345, in hstack
    return _nx.concatenate(arrs, 1)
  File "<__array_function__ internals>", line 180, in concatenate
ValueError: need at least one array to concatenate

need at least one array to concatenate
>>> import pyopencl.array as cla
>>> cla.hstack([])
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/home/kgk2/projects/ceesd/pyopencl/pyopencl/array.py", line 2700, in hstack
    return empty(queue, (), dtype=np.float64)
  File "/home/kgk2/projects/ceesd/pyopencl/pyopencl/array.py", line 580, in __init__
    self.base_data = cl.Buffer(
TypeError: __init__(): incompatible constructor arguments. The following argument types are supported:
    1. pyopencl._cl.Buffer(context: pyopencl._cl.Context, flags: int, size: int = 0, hostbuf: object = None)

Invoked with: None, 1, 8

__init__(): incompatible constructor arguments. The following argument types are supported:
    1. pyopencl._cl.Buffer(context: pyopencl._cl.Context, flags: int, size: int = 0, hostbuf: object = None)

Invoked with: None, 1, 8

[inducer]

LGTM, thanks!

[inducer]

https://pypi.org/project/pyopencl/2021.2.12/, should wind its way to conda soon.