sim: Use extern for these structs to generate a linkage

Fixes:
duplicate symbol _ts102221_fcp_vals in:
    .libs/core.o
    .libs/card_fs_usim.o
duplicate symbol _pcsc_reader_ops in:
    .libs/reader.o
    .libs/card_fs_usim.o
diff --git a/include/osmocom/sim/sim.h b/include/osmocom/sim/sim.h
index 02cdcad..bb4b7d8 100644
--- a/include/osmocom/sim/sim.h
+++ b/include/osmocom/sim/sim.h
@@ -294,7 +294,7 @@
 char *osim_print_sw(const struct osim_card_hdl *ch, uint16_t sw_in);
 
 extern const struct tlv_definition ts102221_fcp_tlv_def;
-const struct value_string ts102221_fcp_vals[14];
+extern const struct value_string ts102221_fcp_vals[14];
 
 /* 11.1.1.3 */
 enum ts102221_fcp_tag {