alloc: make small_page_bits() function rather than large_page_bits()
[ccan] / ccan / alloc /
drwxr-xr-x   ..
-rw-r--r-- 2805 _info
-rw-r--r-- 29190 alloc.c
-rw-r--r-- 4386 alloc.h
drwxr-xr-x - test