Add extra config flags for binutils

Signed-off-by: David Oberhollenzer <david.oberhollenzer@tele2.at>

docs/build.md

@@ -204,6 +204,7 @@ Currently, the following variables are used:
 * `GCC_CPU` specifies the target processor for GCC.
 * `GCC_EXTRACFG` extra configure arguments passed to GCC. For instance, this
   may contain FPU configuration for ARM targets.
+* `BINUTILS_EXTRACFG` extra configure arguments passed to binutils.
 * `LINUX_TGT` contains the space seperated make targets for the generic,
   main line, LTS kernel package.
 * `CPU_IS_64BIT` is set to `yes` for 64 bit CPUs. This is needed for some

layer/bsp-alix/TOOLCHAIN

@@ -5,6 +5,7 @@ GCC_CPU="i686"
 CPU_IS_64BIT="no"
 
 GCC_EXTRACFG="--disable-libmpx"
+BINUTILS_EXTRACFG=""
 
 LINUXPKG="linux"
 LINUX_TGT="bzImage modules"

layer/bsp-qemu64/TOOLCHAIN

@@ -5,6 +5,7 @@ GCC_CPU="x86-64"
 CPU_IS_64BIT="yes"
 
 GCC_EXTRACFG="--enable-libmpx"
+BINUTILS_EXTRACFG=""
 
 LINUXPKG="linux"
 LINUX_TGT="bzImage"

layer/bsp-rpi3/TOOLCHAIN

@@ -5,6 +5,7 @@ GCC_CPU="armv6"
 CPU_IS_64BIT="no"
 
 GCC_EXTRACFG="--with-float=hard --with-fpu=neon-vfpv3"
+BINUTILS_EXTRACFG=""
 
 LINUXPKG="linux-rpi3"
 LINUX_TGT="zImage dtbs modules"

pkg/tc-binutils/build

@@ -10,7 +10,7 @@ prepare() {
 }
 
 build() {
-	local extra=""
+	local extra="$BINUTILS_EXTRACFG"
 
 	$1/configure --prefix="$TCDIR" --target="$TARGET" --disable-nls \
 		     --with-sysroot="$TCDIR/$TARGET" --disable-multilib \