We often try to open a file for reading whose existence is
optional, and silently ignore errors from open/fopen; report such
errors if they are not due to missing files.
* nd/fopen-errors:
mingw_fopen: report ENOENT for invalid file names
mingw: verify that paths are not mistaken for remote nicknames
log: fix memory leak in open_next_file()
rerere.c: move error_errno() closer to the source system call
print errno when reporting a system call error
wrapper.c: make warn_on_inaccessible() static
wrapper.c: add and use fopen_or_warn()
wrapper.c: add and use warn_on_fopen_errors()
config.mak.uname: set FREAD_READS_DIRECTORIES for Darwin, too
config.mak.uname: set FREAD_READS_DIRECTORIES for Linux and FreeBSD
clone: use xfopen() instead of fopen()
use xfopen() in more places
git_fopen: fix a sparse 'not declared' warning