Remove ephemeral mutexes from the prof machinery, and remove
malloc_mutex_destroy(). This simplifies mutex management on systems
that call malloc()/free() inside pthread_mutex_{create,destroy}().
Add atomic_*_u() for operation on unsigned values.
Fix prof_printf() to call malloc_vsnprintf() rather than
malloc_snprintf().
Program-generate small size class tables for all valid combinations of
LG_TINY_MIN, LG_QUANTUM, and PAGE_SHIFT. Use the appropriate table to generate
all relevant data structures, and remove the distinction between
tiny/quantum/cacheline/subpage bins.
Remove --enable-dynamic-page-shift. This option didn't prove useful in
practice, and it prevented optimizations.
Add Tilera architecture support.
