Redundant function calls

[FrankHB]

In "source/file_allocation_table.c":

uint32_t _FAT_fat_lastCluster (PARTITION* partition, uint32_t cluster) {
    while ((_FAT_fat_nextCluster(partition, cluster) != CLUSTER_FREE) && (_FAT_fat_nextCluster(partition, cluster) != CLUSTER_EOF)) {
        cluster = _FAT_fat_nextCluster(partition, cluster);
    }
    return cluster;
}

It seems that mutiple '_FAT_fat_nextCluster' calls can be merged.