fix gcc 4.6 warning -Wunused-but-set-variable in crypt-gpgme.c

fix gcc 4.6 warning -Wunused-but-set-variable in crypt-gpgme.c

crypt-gpgme.c: In function 'show_one_sig_status':
crypt-gpgme.c:1311:21: warning: variable 'uid' set but not used [-Wunused-but-set-variable]
crypt-gpgme.c: In function 'pgp_gpgme_application_handler':
crypt-gpgme.c:2285:27: warning: variable 'anywarn' set but not used [-Wunused-but-set-variable]
crypt-gpgme.c:2159:8: warning: variable 'start_pos' set but not used [-Wunused-but-set-variable]
crypt-gpgme.c: In function 'crypt_getkeybystr':
crypt-gpgme.c:4094:7: warning: variable 'match' set but not used [-Wunused-but-set-variable]

Signed-off-by: Olaf Hering <olaf@aepfle.de>