[PATCH] CLEANUP: Fix typos in the http subsystem

[Joseph Herlant]

Hi,

The attached patch fixes typos in code comment of the http subsystem.
Note that I included the changes for those 4 files in it as I think
they probably belong to the same subsystem, let me know if it's not
the case:
* src/flt_http_comp.c
* src/http.c
* src/http_conv.c
* src/http_fetch.c

Thanks,
Joseph