Specify gawk instead of awk for asorti()

Author: hackerb9

m100-sanity

@@ -2,7 +2,7 @@
 
 # Sanitize a BASIC listing so that all lines are in order and no line
 # numbers are duplicated.
-awk '
+gawk '
 /^[ \t]*[0-9]/ {
     n = int($0);
     lines[n] = $0;