MIPS: SGI-IP27: No need for kmalloc.h

SGI-IP27 is always cache coherent so we can use generic kmalloc.h and
remove the ip27 specific one.
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/include/asm/mach-ip27/kmalloc.h

-#ifndef __ASM_MACH_IP27_KMALLOC_H
-#define __ASM_MACH_IP27_KMALLOC_H
-
-/*
- * All happy, no need to define ARCH_DMA_MINALIGN
- */
-
-#endif /* __ASM_MACH_IP27_KMALLOC_H */