[Libc] add specs for rand48 and related functions

share/libc/stdlib.h

tests/builtins/oracle/Longinit_sequencer.res.oracle

tests/builtins/oracle/free.res.oracle

tests/builtins/oracle/linked_list.0.res.oracle

tests/builtins/oracle/linked_list.1.res.oracle

tests/builtins/oracle/linked_list.2.res.oracle

tests/builtins/oracle/malloc-size-zero.0.res.oracle

tests/builtins/oracle/malloc-size-zero.1.res.oracle

tests/builtins/oracle/realloc.res.oracle

tests/builtins/oracle/realloc_multiple.0.res.oracle

tests/builtins/oracle/realloc_multiple.1.res.oracle

tests/builtins/oracle/strnlen.res.oracle

tests/libc/oracle/coverage.res.oracle

tests/libc/oracle/fc_libc.0.res.oracle

tests/libc/oracle/fc_libc.1.res.oracle

tests/libc/oracle/netdb_c.res.oracle

tests/libc/oracle/stdlib_h.res.oracle

tests/libc/stdlib_h.c

tests/value/oracle/gauges.res.oracle