Implement pvalloc replacement

Despite being an obsolete function, pvalloc is still present in GLIBC and should
work correctly when jemalloc replaces libc allocator.

include/jemalloc/internal/hook.h

@@ -55,6 +55,7 @@ enum hook_alloc_e {
 	hook_alloc_calloc,
 	hook_alloc_memalign,
 	hook_alloc_valloc,
+	hook_alloc_pvalloc,
 	hook_alloc_mallocx,
 
 	/* The reallocating functions have both alloc and dalloc variants */