ice: add dynamic interrupt allocation

Currently driver can only allocate interrupt vectors during init phase by
calling pci_alloc_irq_vectors. Change that and make use of new
pci_msix_alloc_irq_at/pci_msix_free_irq API and enable to allocate and free
more interrupts after MSIX has been enabled. Since not all platforms
supports dynamic allocation, check it with pci_msix_can_alloc_dyn.

Extend the tracker to keep track how many interrupts are allocated
initially so when all such vectors are already used, additional interrupts
are automatically allocated dynamically. Remember each interrupt allocation
method to then free appropriately. Since some features may require
interrupts allocated dynamically add appropriate VSI flag and take it into
account when allocating new interrupt.

Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

ice: track interrupt vectors with xarray

Replace custom interrupt tracker with generic xarray data structure.
Remove all code responsible for searching for a new entry with xa_alloc,
which always tries to allocate at the lowes possible index. As a result
driver is always using a contiguous region of the MSIX vector table.

New tracker keeps ice_irq_entry entries in xarray as opaque for the rest
of the driver hiding the entry details from the caller.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

ice: add individual interrupt allocation

Currently interrupt allocations, depending on a feature are distributed
in batches. Also, after allocation there is a series of operations that
distributes per irq settings through that batch of interrupts.

Although driver does not yet support dynamic interrupt allocation, keep
allocated interrupts in a pool and add allocation abstraction logic to
make code more flexible. Keep per interrupt information in the
ice_q_vector structure, which yields ice_vsi::base_vector redundant.
Also, as a result there are a few functions that can be removed.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Michal Swiatkowski <michal.swiatkowski@linux.intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

ice: move interrupt related code to separate file

Keep interrupt handling code in a dedicated file. This helps keep driver
structured better and prepares for more functionality added to this file.

Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Piotr Raczynski <piotr.raczynski@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>