Make out of tree build testing possible

tests/verilog/dynamic_range_lhs.sh

@@ -7,7 +7,7 @@ run() {
     right=$4
     echo "a=$alt s=$span l=$left r=$right"
 
-    ../../yosys -q \
+    ${YOSYS} -q \
         -DALT=$alt \
         -DSPAN=$span \
         -DLEFT=$left \

tests/verilog/local_include.sh

@@ -3,7 +3,7 @@
 set -eu
 
 # only works with read_verilog
-yosys='../../yosys -f verilog'
+yosyscmd="${YOSYS} -f verilog"
 test='-p hierarchy'
 subdir=subdir
 source=local_include.v
@@ -11,20 +11,20 @@ include=temp_foo.v
 
 # no include file should fail
 rm -f $include
-echo "logger -expect error $include 1; read_verilog $source" | $yosys
+echo "logger -expect error $include 1; read_verilog $source" | $yosyscmd
 
 # both files local
 echo 'module foo (input a, output b); assign b = a; endmodule' > $include
-$yosys $test $source
+$yosyscmd $test $source
 
 # include local to cwd
 mkdir -p $subdir
 cp $source $subdir
-$yosys $test $subdir/$source
+$yosyscmd $test $subdir/$source
 
 # include local to source
 mv $include $subdir
-$yosys $test $subdir/$source
+$yosyscmd $test $subdir/$source
 
 # include local to source, and source is given as an absolute path
-$yosys $test $(pwd)/$subdir/$source
+$yosyscmd $test $(pwd)/$subdir/$source