ppc: Rename current DAWR macros and variables

Power10 is introducing second DAWR. Use real register names (with
suffix 0) from ISA for current macros and variables used by Qemu.

One exception to this is KVM_REG_PPC_DAWR[X]. This is from kernel
uapi header and thus not changed in kernel as well as Qemu.

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20210412114433.129702-3-ravi.bangoria@linux.ibm.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>