fix(patches): dyn upstream keepalive

[chronolaw]

See https://github.com/Kong/kong/issues/9582, test cases: https://github.com/Kong/kong/pull/9856.

The point is cpool_crc32 in C land.

balancer.lua

• remove the usage of crc32 hash
• pass cpool_name cpool_name_len to C land
• default pool name is an empty string

ngx_http_lua_balancer.c

• remove field crc32 and cpool_crc32
• new field cpool_name to store pool name string
• ngx_http_lua_ffi_balancer_set_current_peer: allocate memory and copy pool name
• ngx_http_lua_ffi_balancer_enable_keepalive: set default pool name to bp->host
• ngx_http_lua_balancer_create_keepalive_pool:
  • use pool name to index upool
  • allocate memory with lua_newuserdata, copy pool name, then set to upool
• ngx_http_lua_balancer_get_keepalive_pool: use pool name to index upool
• ngx_http_lua_balancer_free_keepalive_pool: get pool name and set to nil

[chronolaw]

We have turned to the new bazel build system, so patches should be there.