Issue building the SD Card test in ARM toolchain

[matthewelse]

There is a problem building the SD Card test using:

python workspace_tools\make.py -t ARM -m LPC1768 -n MBED_A12

When I compile this in ARM, it throws up lots of errors,

[ERROR] Error: L6218E: Undefined symbol gpio_init (referred from test_env.o).
Error: L6218E: Undefined symbol wait (referred from test_env.o).
Error: L6218E: Undefined symbol mbed::SPI::write(int) (referred from SDFileSyste
m.o).
Error: L6218E: Undefined symbol mbed::SPI::frequency(int) (referred from SDFileS
ystem.o).
Error: L6218E: Undefined symbol mbed::SPI::SPI(PinName, PinName, PinName) (refer
red from SDFileSystem.o).
Error: L6218E: Undefined symbol wait_ms (referred from SDFileSystem.o).
Error: L6218E: Undefined symbol typeinfo for mbed::FileSystemLike (referred from
 FATFileSystem.o).
Error: L6218E: Undefined symbol mbed::FileHandle::~FileHandle__sub_object() (ref
erred from FATFileHandle.o).
Error: L6218E: Undefined symbol typeinfo for mbed::FileHandle (referred from FAT
FileHandle.o).
Error: L6218E: Undefined symbol vtable for mbed::FileHandle (referred from FATFi
leHandle.o).
Error: L6218E: Undefined symbol mbed::FileSystemLike::FileSystemLike__sub_object
(const char*) (referred from FATFileSystem.o).
Error: L6218E: Undefined symbol mbed::FileSystemLike::~FileSystemLike__sub_objec
t() (referred from FATFileSystem.o).

On the other hand, when I use GCC_ARM, there are no errors when building for the LPC1768