stdlib: Removing incorrect requires.

This change removes call to requires for checking isa_required
in AbstractProcessor.__init__() and
AbstractGeneratorCore.__init__(). The previous calls would cause
incorrect errors when running generators with any isa other than
NULL.

Change-Id: I303f1e48a7d5649bbe19e0f52ace808225a771c5
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/61289
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Maintainer: Jason Lowe-Power <power.jg@gmail.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>

src/python/gem5/components/processors/abstract_generator_core.py

@@ -54,7 +54,6 @@ class AbstractGeneratorCore(AbstractCore):
         # TODO: Remove the CPU Type parameter. This not needed.
         # Jira issue here: https://gem5.atlassian.net/browse/GEM5-1031
         super().__init__(CPUTypes.TIMING)
-        requires(isa_required=ISA.NULL)
         self.port_end = PortTerminator()
 
     @overrides(AbstractCore)

src/python/gem5/components/processors/abstract_processor.py

@@ -49,8 +49,6 @@ class AbstractProcessor(SubSystem):
         assert len(set(core.get_isa() for core in cores)) == 1
         self._isa = cores[0].get_isa()
 
-        requires(isa_required=self._isa)
-
         self.cores = cores
 
     def get_num_cores(self) -> int: