libc,libthr: Remove __pthread_distribute_static_tls

[jrtc27]

Summary

This private API is no longer used by rtld-elf so can be removed.

[kib]

lib/libc/gen/libc_interposing_table.c

45

My opinion is that we should keep the slot unused if we remove the interposer. If anything, this would make the upgrades easier, and not break half-upgraded systems to the state where /rescue must be used.

[jrtc27]

lib/libc/gen/libc_interposing_table.c

45

As in turn it into __INTERPOS_reserved0, and allow it to be reused after one release cycle when we know the slot definitely won't be in use by system libraries any more?

[kib]

lib/libc/gen/libc_interposing_table.c

45

Not sure about reuse, but for now yes, just reserve the index in the table.

[jrtc27]

Reserve rather than remove interposing slot

[jrtc27]

lib/libc/include/libc_private.h

252

Could do INTERPOS__reserved42 too to document its (decimal) value, like how it's MAP_RESERVED%04X