This commit removes some ::rtl:: prefixes and RTL_CONSTASCII_STRINGPARAM,
 RTL_CONSTASCII_USTRINGPARAM macros in IO.

Change-Id: I823fcdfe46d4d4093118f6eaab89c1ce42883a6c
Signed-off-by: José Guilherme Vanz <guilherme.sft@gmail.com>
Reviewed-on: https://gerrit.libreoffice.org/1194Reviewed-by: Olivier Hallot <olivier.hallot@alta.org.br>
Tested-by: Olivier Hallot <olivier.hallot@alta.org.br>