xserver_xorg-server: add upstream patches to fix build issue

Fixes the following build issue with gcc 4.6:

  LINK  Xfbdev
.../host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.6.1/../../../../arm-none-linux-gnueabi/bin/ld: ../../../os/.libs/libos.a(backtrace.o): undefined reference to symbol 'dladdr@@GLIBC_2.4'
.../host/opt/ext-toolchain/bin/../lib/gcc/arm-none-linux-gnueabi/4.6.1/../../../../arm-none-linux-gnueabi/bin/ld: note: 'dladdr@@GLIBC_2.4' is defined in DSO .../host/usr/arm-unknown-linux-gnueabi/sysroot/lib/libdl.so.2 so try adding it to the linker command line
.../host/usr/arm-unknown-linux-gnueabi/sysroot/lib/libdl.so.2: could not read symbols: Invalid operation

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>