Fix compiler with -Werror,-Wpointer-sign

Fix compiler error with -Werror,-Wpointer-sign

R=rsleevi@chromium.org
BUG=380925

[wtc, 2014-06-05 23:51:34]

The compiler warnings are:

../../third_party/nss/nss/lib/certdb/genname.c:1614:37: error: initializing
'unsigned char *' with an expression of type 'char *' converts between pointers
to integer types with different sign [-Werror,-Wpointer-sign]
  const SECItem anssi_subject = {0, (char *) rawANSSISubject,
                                    ^~~~~~~~~~~~~~~~~~~~~~~~
../../third_party/nss/nss/lib/certdb/genname.c:1616:41: error: initializing
'unsigned char *' with an expression of type 'char *' converts between pointers
to integer types with different sign [-Werror,-Wpointer-sign]
  const SECItem permitFranceGovNC = {0, (char *) constraintFranceGov,
                                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~

[Ryan Sleevi, 2014-06-06 00:04:35]

A slightly tweak to commit message, but LGTM

[wtc, 2014-06-06 00:42:15]

The CQ bit was checked by wtc@chromium.org

[commit-bot: I haz the power, 2014-06-06 00:42:26]

CQ is trying da patch. Follow status at
 https://chromium-status.appspot.com/cq/wtc@chromium.org/316353002/1

[commit-bot: I haz the power, 2014-06-06 00:42:52]

Change committed as 275283