BLOCK_COUNT cannot be less than 10

[joshuajylin]

I found that when BLOCK_COUNT is less than 10, LfsFilesystem::format will return -28 (NO_SPACE).

I tried both flash and ram implementations, both are the same.

I'm developing in no_std environment and have the following line in my Cargo.toml.

littlefs2 = { version = "0.6.1", features = ["c-stubs"] }