ppp: bump to 2.4.6

package/network/services/ppp/Makefile

...etwork/services/ppp/patches/100-debian_ip-ip_option.patch

package/network/services/ppp/patches/105-debian_demand.patch

...etwork/services/ppp/patches/110-debian_defaultroute.patch

.../services/ppp/patches/120-debian_ipv6_updown_option.patch

.../network/services/ppp/patches/140-pppoe_compile_fix.patch

package/network/services/ppp/patches/200-makefile.patch

package/network/services/ppp/patches/201-mppe_mppc_1.1.patch

package/network/services/ppp/patches/202-no_strip.patch

package/network/services/ppp/patches/203-opt_flags.patch

...ork/services/ppp/patches/205-no_exponential_timeout.patch

package/network/services/ppp/patches/207-lcp_mtu_max.patch

...k/services/ppp/patches/300-filter-pcap-includes-lib.patch

.../network/services/ppp/patches/310-precompile_filter.patch

...network/services/ppp/patches/320-custom_iface_names.patch

...pp/patches/321-multilink_support_custom_iface_names.patch

...ork/services/ppp/patches/400-simplify_kernel_checks.patch

...age/network/services/ppp/patches/401-no_record_file.patch

package/network/services/ppp/patches/403-no_wtmp.patch

...etwork/services/ppp/patches/405-no_multilink_option.patch