hw/block/pflash: Simplify trace_pflash_io_read/write()

Call the read() trace function after the value is set, so we can
log the returned value.
Rename the I/O trace functions with '_io_' in their name.

Reviewed-by: Stephen Checkoway <stephen.checkoway@oberlin.edu>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190627202719.17739-3-philmd@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
3 files changed