Clean up interface to PM and VFS

- introduce new call numbers, names, and field aliases;
- initialize request messages to zero for all ABI calls;
- format callnr.h in the same way as com.h;
- redo call tables in both servers;
- remove param.h namespace pollution in the servers;
- make brk(2) go to VM directly, rather than through PM;
- remove obsolete BRK, UTIME, and WAIT calls;
- clean up path copying routine in VFS;
- move remaining system calls from libminlib to libc;
- correct some errno-related mistakes in libc routines.

Change-Id: I2d8ec5d061cd7e0b30c51ffd77aa72ebf84e2565

lib/libsys/Makefile

@@ -85,7 +85,6 @@ SRCS+=  \
 	taskcall.c \
 	tickdelay.c \
 	timers.c \
-	vm_brk.c \
 	vm_cache.c \
 	vm_exit.c \
 	vm_fork.c \