net: ipa: kill gsi->virt_raw

Starting at IPA v4.5, almost all GSI registers had their offsets
changed by a fixed amount (shifted downward by 0xd000).  Rather than
defining offsets for all those registers dependent on version, an
adjustment was applied for most register accesses.  This was
implemented in commit cdeee49f ("net: ipa: adjust GSI register
addresses").  It was later modified to be a bit more obvious about
the adjusment, in commit 571b1e7e ("net: ipa: use a separate
pointer for adjusted GSI memory").

We now are able to define every GSI register with its own offset, so
there's no need to implement this special adjustment.

So get rid of the "virt_raw" pointer, and just maintain "virt" as
the (non-adjusted) base address of I/O mapped GSI register memory.

Redefine the offsets of all GSI registers (other than the INTER_EE
ones, which were not subject to the adjustment) for IPA v4.5+,
subtracting 0xd000 from their defined offsets instead.

Move the ERROR_LOG and ERROR_LOG_CLR definitions further down in the
register definition files so all registers are defined in order of
their offset.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>