gcc: add patch to fix EABI for armv4t

As pointed out by Martin GUY, gcc incorrectly generates armv5t
instrcutions for EABI, even for cores that are an armv4t.
The new patch (for the 4.3 series) fixes the problem by downgrading
the default CPU for EABI to being an armv4t core.

 # x86 specific options

 config ARCH_x86

     select ARCH_USE_MMU

     select ARCH_SUPPORT_ARCH

     select ARCH_SUPPORT_CPU

     select ARCH_SUPPORT_TUNE

     help

       The x86 architecture, as defined by:

         http://www.intel.com/