net: Remove env_get_ip helper() function

Currently, we have the function env_get_ip which takes an IP address
in string form and returns a struct in_addr representation of that
address. It is however little used and means that a number of places
indirectly (and unclearly) get <env.h> via <net.h>. To clean this up
start by replacing env_get_ip() calls with string_to_ip() calls. This is
generally a no-op as env_get_ip(str) is an inline of
string_to_ip(env_get(str)) but in a few cases we can or already have
stored the result of env_get(str) and can save the additional call.

Signed-off-by: Tom Rini <trini@konsulko.com>

include/net-common.h

@@ -456,19 +456,6 @@ void net_process_received_packet(uchar *in_packet, int len);
  */
 int update_tftp(ulong addr, char *interface, char *devstring);
 
-/**
- * env_get_ip() - Convert an environment value to an ip address
- *
- * @var: Environment variable to convert. The value of this variable must be
- *	in the format a.b.c.d, where each value is a decimal number from
- *	0 to 255
- * Return: IP address, or 0 if invalid
- */
-static inline struct in_addr env_get_ip(char *var)
-{
-	return string_to_ip(env_get(var));
-}
-
 int net_init(void);
 
 /* Called when a network operation fails to know if it should be re-tried */