MAINT: Fix LGTM.com warning
MAINT: Fix LGTM.com warning

Comparison result is always the same
Comparison is always false because bufferSize >= 16384.

Indeed Dragon4_Scratch is defined as:

	typedef struct {
	    BigInt bigints[BIGINT_DRAGON4_GROUPSIZE];
	    char repr[16384];
	} Dragon4_Scratch;

Therefore sizeof(scratch->repr) is 16384. It cannot be 0 or 1.
Make bufferSize const for clarity.

rgommers/numpy,numpy/numpy,jakirkham/numpy,pdebuyl/numpy,rgommers/numpy,charris/numpy,endolith/numpy,seberg/numpy,seberg/numpy,mattip/numpy,charris/numpy,simongibbons/numpy,mattip/numpy,mhvk/numpy,mhvk/numpy,mhvk/numpy,anntzer/numpy,jakirkham/numpy,jakirkham/numpy,numpy/numpy,simongibbons/numpy,mattip/numpy,mhvk/numpy,pdebuyl/numpy,rgommers/numpy,charris/numpy,endolith/numpy,jakirkham/numpy,charris/numpy,anntzer/numpy,anntzer/numpy,endolith/numpy,simongibbons/numpy,simongibbons/numpy,jakirkham/numpy,seberg/numpy,rgommers/numpy,numpy/numpy,mhvk/numpy,mattip/numpy,seberg/numpy,endolith/numpy,simongibbons/numpy,anntzer/numpy,pdebuyl/numpy,numpy/numpy,pdebuyl/numpy