toolchain/wrapper.sh: fix remaining shellcheck warnings

Fixes following warnings:

 In target/toolchain/files/wrapper.sh line 18:
 REALNAME=$(readlink -f $0)
                        ^-- SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 20:
 REALNAME_BASE=$(basename $REALNAME)
                          ^-------^ SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 21:
 REALNAME_DIR=$(dirname $REALNAME)
                        ^-------^ SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 74:
 		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $GCC_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_CFLAGS $TARGET_ROOTFS_CFLAGS "$@"
                     ^-----------------------^ SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 77:
 		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $LD_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_LDFLAGS "$@"
                      ^-----------------------^ SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 80:
 		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $TARGET_FUNDAMENTAL_ASFLAGS "$@"
                      ^-----------------------^ SC2086: Double quote to prevent globbing and word splitting.
 --
 In target/toolchain/files/wrapper.sh line 83:
 		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin "$@"
                      ^-----------------------^ SC2086: Double quote to prevent globbing and word splitting.

Signed-off-by: Petr Štetiar <[email protected]>

target/toolchain/files/wrapper.sh

@@ -15,10 +15,10 @@
 #
 
 PROGNAME=$0
-REALNAME=$(readlink -f $0)
+REALNAME=$(readlink -f "$0")
 
-REALNAME_BASE=$(basename $REALNAME)
-REALNAME_DIR=$(dirname $REALNAME)
+REALNAME_BASE=$(basename "$REALNAME")
+REALNAME_DIR=$(dirname "$REALNAME")
 
 TARGET_FUNDAMENTAL_ASFLAGS=''
 TARGET_FUNDAMENTAL_CFLAGS=''
@@ -30,7 +30,7 @@ TARGET_TOOLCHAIN_TRIPLET=${REALNAME_BASE%-*}
 BINARY=${PROGNAME##*-}
 
 # Parse our tool name, splitting it at '-' characters.
-IFS=- read -r TOOLCHAIN_ARCH TOOLCHAIN_BUILDROOT TOOLCHAIN_OS TOOLCHAIN_PLATFORM PROGNAME << EOF
+IFS=- read -r _ _ _ TOOLCHAIN_PLATFORM PROGNAME << EOF
 $REALNAME_BASE
 EOF
 
@@ -71,16 +71,16 @@ esac
 #
 case $BINARY in
 	cc|gcc|g++|c++|cpp)
-		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $GCC_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_CFLAGS $TARGET_ROOTFS_CFLAGS "$@"
+		exec "$TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin" $GCC_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_CFLAGS $TARGET_ROOTFS_CFLAGS "$@"
 		;;
 	ld)
-		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $LD_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_LDFLAGS "$@"
+		exec "$TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin" $LD_SYSROOT_FLAGS $TARGET_FUNDAMENTAL_LDFLAGS "$@"
 		;;
 	as)
-		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin $TARGET_FUNDAMENTAL_ASFLAGS "$@"
+		exec "$TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin" $TARGET_FUNDAMENTAL_ASFLAGS "$@"
 		;;
 	*)
-		exec $TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin "$@"
+		exec "$TARGET_TOOLCHAIN_TRIPLET-$BINARY.bin" "$@"
 		;;
 esac