Fix parsing of smartcardoptions config

With the previous code, a trailing newline would result in an empty space being part of the list. When this is passed to keytool, it fails with "Illegal option: ".

Instead of doing overly complicated regex based string substitution followed by parametrized splitting, we can simply use .split() without any parameters, and Python will automatically strip any whitespace.

Example:

>>> import yaml, re
>>> parsed = yaml.safe_load('''
... smartcardoptions: |
...   -storetype PKCS11
...   -providerClass sun.security.pkcs11.SunPKCS11
...   -providerArg /etc/pkcs11_java.cfg
...
... ''')
>>> parsed['smartcardoptions']
'-storetype PKCS11\n-providerClass sun.security.pkcs11.SunPKCS11\n-providerArg /etc/pkcs11_java.cfg\n'

With the old approach (note the empty string at the end):

>>> re.sub(r'\s+', r' ', parsed['smartcardoptions']).split(' ')
['-storetype', 'PKCS11', '-providerClass', 'sun.security.pkcs11.SunPKCS11', '-providerArg', '/etc/pkcs11_java.cfg', '']

With the fix:

>>> parsed['smartcardoptions'].split()
['-storetype', 'PKCS11', '-providerClass', 'sun.security.pkcs11.SunPKCS11', '-providerArg', '/etc/pkcs11_java.cfg']