modpost uses grab_file() to open a file, but it is not suitable for
a text file because the mmap'ed file is not terminated by null byte.
Actually, I see some issues for the use of grab_file().
The new helper, read_text_file() loads the whole file content into a
malloc'ed buffer, and appends a null byte. Then, get_line() reads
each line.
To handle text files, I intend to replace as follows:
grab_file() -> read_text_file()
get_new_line() -> get_line()
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
ac5100f543