bin/55633: awk gets FPE_FLTDIV when building librump on an alpha builder

[thorpej%me.com@localhost]

>Number:         55633
>Category:       bin
>Synopsis:       awk gets FPE_FLTDIV when building librump on an alpha builder
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Mon Aug 31 17:30:00 +0000 2020
>Originator:     Jason Thorpe
>Release:        netbsd-current as of 31 Aug, 2020
>Organization:
RISCy Business
>Environment:
NetBSD/alpha running netbsd-9-stable userland and 9.99.71 kernel
>Description:
Host system is DS25 running a netbsd-9-stable userland and a netbsd-current kernel.  Standard netbsd-current build tools were build using build.sh.

When building librump, the awk script that supports rump symbol renaming encounters:

/home/thorpej/nbsd/tools/bin/nbawk: floating point exception: Floating point divide by zero
 input record number 38, file 
 source line number 1
/home/thorpej/nbsd/tools/bin/nbawk: floating point exception: Floating point divide by zero
 input record number 36, file 
 source line number 1
.
.
.

...which causes the symbol renaming to be incomplete, leading to subsequent rump-related build failures.

Substituting the host awk (netbsd-9-stable /usr/bin/awk) fixes the issue.
>How-To-Repeat:
Use build.sh to bootstrap the build tools on a NetBSD/alpha build host, and attempt to build librump.
>Fix: