bcf_set_variant_type does not correct set type BND for reverse strand breakends

[mp15]

htslib/vcf.c

Lines 4182 to 4199 in 58d9f60

	const char *r = ref, *a = alt;
	while (*r && *a && toupper_c(*r)==toupper_c(*a) ) { r++; a++; } // unfortunately, matching REF,ALT case is not guaranteed
	if ( *a && !*r )
	{
	if ( *a==']' || *a=='[' ) { var->type = VCF_BND; return; }
	while ( *a ) a++;
	var->n = (a-alt)-(r-ref); var->type = VCF_INDEL; return;
	}
	else if ( *r && !*a )
	{
	while ( *r ) r++;
	var->n = (a-alt)-(r-ref); var->type = VCF_INDEL; return;
	}
	else if ( !*r && !*a )
	{
	var->n = 0; var->type = VCF_REF; return;
	}

A forward strand breakend like:
REF N
ALT N]16:33625444]
will be correctly detected as VCF_BND.

A reverse strand breakend like:
REF N
ALT [16:33531168[N
will be incorrectly detected as VCF_INDEL.

This is because it should be working right to left for the reverse strand INDEL.