[security-kit] dev-libs/pkcs11-helper-1.25.1 doesn't emerge with USE flag `nss` and `gnutls`

Compilation of `dev-libs/pkcs11-helper-1.25.1` fails with USE flag `nss` and `gnutls`:

```
/bin/sh ../libtool --tag=CC --mode=compile x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c -o pkcs11h-threading.lo pkcs11h-threading.c
/bin/sh ../libtool --tag=CC --mode=compile x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c -o pkcs11h-util.lo pkcs11h-util.c
/bin/sh ../libtool --tag=CC --mode=compile x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c -o pkcs11h-session.lo pkcs11h-session.c
In file included from /usr/include/nss/keythi.h:11,
from /usr/include/nss/cert.h:21,
from _pkcs11h-crypto-nss.c:58:
/usr/include/nss/secmodt.h:79:5: error: unknown type name ‘CK_NSS_GetFIPSStatus’
79 | CK_NSS_GetFIPSStatus fipsIndicator;
| ^~~~~~~~~~~~~~~~~~~~
/bin/sh ../libtool --tag=CC --mode=compile x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c -o pkcs11h-token.lo pkcs11h-token.c
/bin/sh ../libtool --tag=CC --mode=compile x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c -o pkcs11h-certificate.lo pkcs11h-certificate.c
libtool: compile: x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c pkcs11h-threading.c -fPIC -DPIC -o .libs/pkcs11h-threading.o
make[3]: *** [Makefile:597: _pkcs11h-crypto-nss.lo] Error 1
make[3]: *** Waiting for unfinished jobs....
libtool: compile: x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c pkcs11h-certificate.c -fPIC -DPIC -o .libs/pkcs11h-certificate.o
libtool: compile: x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c pkcs11h-util.c -fPIC -DPIC -o .libs/pkcs11h-util.o
libtool: compile: x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c pkcs11h-token.c -fPIC -DPIC -o .libs/pkcs11h-token.o
libtool: compile: x86_64-pc-linux-gnu-gcc -DHAVE_CONFIG_H -I. -I.. -I../include -I../include -mtune=generic -O2 -pipe -I/usr/include/p11-kit-1 -I/usr/include/nss -I/usr/include/nspr -c pkcs11h-session.c -fPIC -DPIC -o .libs/pkcs11h-session.o
make[3]: Leaving directory '/var/tmp/portage/dev-libs/pkcs11-helper-1.25.1/work/pkcs11-helper-1.25.1/lib'
make[2]: *** [Makefile:477: all] Error 2
make[2]: Leaving directory '/var/tmp/portage/dev-libs/pkcs11-helper-1.25.1/work/pkcs11-helper-1.25.1/lib'
make[1]: *** [Makefile:546: all-recursive] Error 1
make[1]: Leaving directory '/var/tmp/portage/dev-libs/pkcs11-helper-1.25.1/work/pkcs11-helper-1.25.1'
make: *** [Makefile:455: all] Error 2
* ERROR: dev-libs/pkcs11-helper-1.25.1::security-kit failed (compile phase):
* emake failed
```

A temporary workaround is disable the two USE flags.

Reproduce the emerge failure with both nss and gnutls enabled, then inspect _pkcs11h-crypto-nss.c around its NSS includes and the referenced /usr/include/nss/secmodt.h declaration. Check the generated lib/Makefile target for _pkcs11h-crypto-nss.lo and confirm the package compiles successfully with both USE flags enabled.

Written by the indexing model from the issue text.