shadow: remove reference to locale env files from login and su

shadow: remove reference to locale env files from login and su

/etc/default/locale missing message appears when login
and running su <user>

qemu0 login[4189]: pam_env(login:session): Unable to open env file: /etc/default/locale: No such file or directory
qemu0 login[4189]: pam_unix(login:session): session opened for user root by LOGIN(uid=0)

qemu0 su[999]: pam_env(su:session): Unable to open env file: /etc/default/locale: No such file or directory
qemu0 su[999]: pam_unix(su:session): session opened for user root by root(uid=0)

This commit remove reference from pam.d/login and pam.d/su
to /etc/default/locale env file to avoid the error messages
as RHEL, fedora does.

(From OE-Core rev: 010ffabfb8631bd4894cc3f1f6f0834f3279f30c)

Signed-off-by: Qiang Chen <qiang.chen@windriver.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>