Stabilize ip_from

[GrigorenkoPV]

Tracking issue: #131360

Stabilizes and const-stabilizes the following APIs:

// core::net
impl Ipv4Addr {
    pub const fn from_octets(octets: [u8; 4]) -> Ipv4Addr;
}
impl Ipv6Addr {
    pub const fn from_octets(octets: [u8; 16]) -> Ipv6Addr;
    pub const fn from_segments(segments: [u16; 8]) -> Ipv6Addr;
}

Closes #131360

@rustbot label +needs-fcp

[rustbot]

r? @Mark-Simulacrum

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[jieyouxu]

r? libs-api

[GrigorenkoPV]

r? libs-api