Fix changes in Env 1.40-1.41 so they work after a clean boot

These relied on calling the GNU.gawk binary, but did so *before* the run path
was guaranteed to point at it. Move that block of lines lower down.

Also remove unused (and commented) Src$Dir definition within the lines that
we move it past.

!Common,feb

@@ -44,6 +44,16 @@ RMEnsure SharedUnixLibrary 1.12 RMLoad <Build$Dir>.Modules.SharedULib
 RMEnsure SharedCLibrary 5.18 RMLoad System:Modules.CLib
 RMEnsure SharedCLibrary 5.18
 
+| This is setup so this can be run multiple times without extending Run$Path
+if "<Build$Setup>" = "" then set Run$Path Build:,Apps:,<Run$Path>
+setmacro Build$Path     <Tools$Dir>.Acorn.,<Tools$Dir>.Build.,<Tools$Dir>.Unix.,<Tools$Dir>.Misc.,<Tools$Dir>.,<Tools$Dir>.DrSmiths.Utilities.
+set BASIC$Path     Build:
+Set Apps$Path      <Build$Dir>.Apps.
+Set Makefiles$Path <Build$Dir>.BuildSys.Makefiles.
+|
+set Install$Dir       <Build$Dir>.Install
+setmacro Install$Path <Install$Dir>.
+
 |
 | Determine whether we have a working or broken amu - if it is working (5.13 or later), the system variable
 | BuildSys$AMU$Fixed will be set to "yes" - otherwise "yes".   To cope with the broken Makefiles in the build
@@ -55,17 +65,6 @@ set alias$amu_machine amu MACHINE=<Machine> LOCALE=<Locale> SYSTEM=<System> BUIL
 if "<BuildSys$AMU$Fixed>"="yes" Then set alias$amu_machine amu -E %%*0
 |
 
-| This is setup so this can be run multiple times without extending Run$Path
-if "<Build$Setup>" = "" then set Run$Path Build:,Apps:,<Run$Path>
-setmacro Build$Path     <Tools$Dir>.Acorn.,<Tools$Dir>.Build.,<Tools$Dir>.Unix.,<Tools$Dir>.Misc.,<Tools$Dir>.,<Tools$Dir>.DrSmiths.Utilities.
-set BASIC$Path     Build:
-Set Apps$Path      <Build$Dir>.Apps.
-Set Makefiles$Path <Build$Dir>.BuildSys.Makefiles.
-|
-|set Src$Dir        <Build$Dir>.Sources
-set Install$Dir       <Build$Dir>.Install
-setmacro Install$Path <Install$Dir>.
-
 | Locate the export directories and set the tool options
 /Build:ToolOptions.<APCS>
 |

!Common.sh

@@ -15,7 +15,6 @@ export PATH
 
 export APPDIR=$BUILDDIR/Apps
 export MAKEFILEDIR=$BUILDDIR/BuildSys/GNUmakefiles
-#export SRCDIR=$BUILDDIR/Sources
 export INSTALLDIR=$BUILDDIR/Install
 
 if [ "$APCS" = "APCS-R" ]; then