The information from the README.md have been merged into the
documentation.
The necessary tools for the sdcard.sh are quite tricky to build. All
necessary information to create an SD image are in the documentation
already. So the script isn't necessary any more.
Update #5088
The default exception handler uses the Save Program Status Register
(SPSR), however, if _ARMV4_Exception_reserved_default() would get
called, the state of this register is unpredictable. Replace potential
calls to _ARMV4_Exception_reserved_default() with an undefined
instruction.
