This commit removes redundant generic-y defines in
arch/arc/include/asm/Kbuild.

It is redundant to define generic-y when arch-specific implementation
exists in arch/$(ARCH)/include/asm/*.h

Remove the following generic-y:

    dma-mapping.h
    fb.h
    kmap_types.h
    pci.h
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>