[MIPS] Remove unused definition of cpu_to_lelongp()

#define SZLONG_MASK 31UL

#define __LL		"ll	"

#define __SC		"sc	"

#define cpu_to_lelongp(x) cpu_to_le32p((__u32 *) (x))

#elif (_MIPS_SZLONG == 64)

#define SZLONG_LOG 6

#define SZLONG_MASK 63UL

#define __LL		"lld	"

#define __SC		"scd	"

#define cpu_to_lelongp(x) cpu_to_le64p((__u64 *) (x))

#endif

/*