Adding ipc_ prefix to ipc primitives

* Also change _orig to _intr for clarity
 * Cleaned up {IPC,KER}VEC
 * Renamed _minix_kernel_info_struct to get_minix_kerninfo
 * Merged _senda.S into _ipc.S
 * Moved into separate files get_minix_kerninfo and _do_kernel_call
 * Adapted do_kernel_call to follow same _ convention as ipc functions
 * Drop patches in libc/net/send.c and libc/include/namespace.h

Change-Id: If4ea21ecb65435170d7d87de6c826328e84c18d0

kernel/proc.h

@@ -178,7 +178,7 @@ struct proc {
 /* Macro to return: on which process is a certain process blocked?
  * return endpoint number (can be ANY) or NONE. It's important to
  * check RTS_SENDING first, and then RTS_RECEIVING, as they could
- * both be on (if a sendrec() blocks on sending), and p_getfrom_e
+ * both be on (if a ipc_sendrec() blocks on sending), and p_getfrom_e
  * could be nonsense even though RTS_RECEIVING is on.
  */
 #define P_BLOCKEDON(p)							\