fix improper variable declaration as a pointer. On two occasions, a gzFile is declared as a pointer, except the type mismatches with the expected type by the gz API, resulting in errors like: . fastq2bfq.c:30:12: error: assignment to ‘struct gzFile_s **’ from incompatible pointer type ‘gzFile’ {aka ‘struct gzFile_s *’} [-Wincompatible-pointer-types] 30 | fp = gzopen(str, "w"); | ^ fastq2bfq.c:36:28: error: assignment to ‘struct gzFile_s **’ from incompatible pointer type ‘gzFile’ {aka ‘struct gzFile_s *’} [-Wincompatible-pointer-types] 36 | fp = gzopen(str, "w"); | ^ fastq2bfq.c:47:25: error: passing argument 1 of ‘gzwrite’ from incompatible pointer type [-Wincompatible-pointer-types] 47 | gzwrite(fp, &i, sizeof(int)); | ^~ | | | struct gzFile_s **
