cpu: add a new instruction type 'Atomic'

This patch adds a new flag named 'Atomic' to support ISA implementations
that use AtomicOpFunctor to handle atomic instructions instead of a
pair of locking load and unlocking store.

Change-Id: I1fbee6e54432396cb49dfc59ad9006b75812d115
Reviewed-on: https://gem5-review.googlesource.com/8187
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Anthony Gutierrez <anthony.gutierrez@amd.com>

arch: ISA parser additions of vector registers

Reiley's update :) of the isa parser definitions. My addition of the
vector element operand concept for the ISA parser. Nathanael's modification
creating a hierarchy between vector registers and its constituencies to the
isa parser.

Some fixes/updates on top to consider instructions as vectors instead of
floating when they use the VectorRF. Some counters added to all the
models to keep faithful counts.

Change-Id: Id8f162a525240dfd7ba884c5a4d9fa69f4050101
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/2706
Reviewed-by: Anthony Gutierrez <anthony.gutierrez@amd.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

revert 5af8f40d8f2c

cpu: implements vector registers

This adds a vector register type. The type is defined as a std::array of a
fixed number of uint64_ts. The isa_parser.py has been modified to parse vector
register operands and generate the required code. Different cpus have vector
register files now.

cpu: Add flag name printing to StaticInst

This patch adds a the member function StaticInst::printFlags to allow all
of an instruction's flags to be printed without using the individual
is... member functions or resorting to exposing the 'flags' vector

It also replaces the enum definition StaticInst::Flags with a
Python-generated enumeration and adds to the enum generation mechanism
in src/python/m5/params.py to allow Enums to be placed in namespaces
other than Enums or, alternatively, in wrapper structs allowing them to
be inherited by other classes (so populating that class's name-space
with the enumeration element names).