POSIX compliance: (most) shell scripts converted to generic shell

Ports/.port_include.sh, Toolchain/BuildIt.sh, Toolchain/UseIt.sh
have been left largely untouched due to use of Bash-exclusive
functions and variables such as $BASH_SOURCE, pushd and popd.

Toolchain/BuildIt.sh

@@ -1,16 +1,18 @@
 #!/bin/bash
 set -e
 
+# This file will need to be run in bash, for now.
+
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
-echo $DIR
+echo "$DIR"
 
 TARGET=i686-pc-serenity
 PREFIX="$DIR/Local"
 SYSROOT="$DIR/../Root"
 
-echo PREFIX is $PREFIX
-echo SYSROOT is $SYSROOT
+echo PREFIX is "$PREFIX"
+echo SYSROOT is "$SYSROOT"
 
 mkdir -p "$DIR/Tarballs"
 
@@ -40,7 +42,7 @@ pushd "$DIR/Tarballs"
         tar -xf "binutils-2.32.tar.gz"
 
         pushd "binutils-2.32"
-            patch -p1 < $DIR/Patches/binutils.patch > /dev/null
+            patch -p1 < "$DIR"/Patches/binutils.patch > /dev/null
         popd
     else
         echo "Skipped extracting binutils"
@@ -51,14 +53,14 @@ pushd "$DIR/Tarballs"
         tar -xf "gcc-8.3.0.tar.gz"
 
         pushd "gcc-8.3.0"
-            patch -p1 < $DIR/Patches/gcc.patch > /dev/null
+            patch -p1 < "$DIR"/Patches/gcc.patch > /dev/null
         popd
     else
         echo "Skipped extracting gcc"
     fi
 popd
 
-mkdir -p $PREFIX
+mkdir -p "$PREFIX"
 
 mkdir -p "$DIR/Build/binutils"
 mkdir -p "$DIR/Build/gcc"
@@ -71,24 +73,24 @@ pushd "$DIR/Build/"
     unset PKG_CONFIG_LIBDIR # Just in case
 
     pushd binutils
-        $DIR/Tarballs/binutils-2.32/configure --prefix=$PREFIX \
-                                              --target=$TARGET \
-                                              --with-sysroot=$SYSROOT \
+        "$DIR"/Tarballs/binutils-2.32/configure --prefix="$PREFIX" \
+                                              --target="$TARGET" \
+                                              --with-sysroot="$SYSROOT" \
                                               --disable-nls || exit 1
-        make -j $MAKEJOBS || exit 1
+        make -j "$MAKEJOBS" || exit 1
         make install || exit 1
     popd
 
     pushd gcc
-        $DIR/Tarballs/gcc-8.3.0/configure --prefix=$PREFIX \
-                                          --target=$TARGET \
-                                          --with-sysroot=$SYSROOT \
+        "$DIR"/Tarballs/gcc-8.3.0/configure --prefix="$PREFIX" \
+                                          --target="$TARGET" \
+                                          --with-sysroot="$SYSROOT" \
                                           --disable-nls \
                                           --with-newlib \
                                           --enable-languages=c,c++ || exit 1
 
         echo "XXX build gcc and libgcc"
-        make -j $MAKEJOBS all-gcc all-target-libgcc || exit 1
+        make -j "$MAKEJOBS" all-gcc all-target-libgcc || exit 1
         echo "XXX install gcc and libgcc"
         make install-gcc install-target-libgcc || exit 1
 

Toolchain/UseIt.sh

@@ -1,4 +1,7 @@
 #!/bin/bash
+
+# This file will need to be run in bash, for now.
+
 DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 export PATH="$DIR/Local/bin:$PATH"
 export TOOLCHAIN="$DIR"