fix PA1.1 oops on boot

fix PA1.1 oops on boot

commit 5e185581d7c46ddd33cd9c01106d1fc86efb9376 upstream.

All PA1.1 systems have been oopsing on boot since

commit f311847c2fcebd81912e2f0caf8a461dec28db41
Author: James Bottomley <James.Bottomley@HansenPartnership.com>
Date:   Wed Dec 22 10:22:11 2010 -0600

    parisc: flush pages through tmpalias space

because a PA2.0 instruction was accidentally introduced into the PA1.1 TLB
insertion interruption path when it was consolidated with the do_alias macro.
Fix the do_alias macro only to use PA2.0 instructions if compiled for 64 bit.
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>