Fix bug in tputc writing to io file

Fix bug in tputc writing to io file

If -f options is enabled then tputc() writes all the data to a file. Actual
code assumes that all the strings in 'c' parameters have always 1 byte
length, but this is not always true, because due to utf-8 encoding some
characters can have a diferent length. So it is necessary pass string length
to tputc in order it can call to write() correctly.
---
 st.c |    8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)