env: Move get/set_default_env() to env.h

Move these functions to the new header file and rename set_default_env()
to env_set_default() so that it has a consistent env_ prefix.

Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/env/common.c b/env/common.c
index db2a033..1d9d0f9 100644
--- a/env/common.c
+++ b/env/common.c
@@ -62,7 +62,7 @@
 	return ret_val;
 }
 
-void set_default_env(const char *s, int flags)
+void env_set_default(const char *s, int flags)
 {
 	if (sizeof(default_environment) > ENV_SIZE) {
 		puts("*** Error - default environment is too large\n\n");
@@ -118,7 +118,7 @@
 		memcpy(&crc, &ep->crc, sizeof(crc));
 
 		if (crc32(0, ep->data, ENV_SIZE) != crc) {
-			set_default_env("bad CRC", 0);
+			env_set_default("bad CRC", 0);
 			return -ENOMSG; /* needed for env_load() */
 		}
 	}
@@ -131,7 +131,7 @@
 
 	pr_err("Cannot import environment: errno = %d\n", errno);
 
-	set_default_env("import failed", 0);
+	env_set_default("import failed", 0);
 
 	return -EIO;
 }
@@ -156,7 +156,7 @@
 	}
 
 	if (buf1_read_fail && buf2_read_fail) {
-		set_default_env("bad env area", 0);
+		env_set_default("bad env area", 0);
 		return -EIO;
 	} else if (!buf1_read_fail && buf2_read_fail) {
 		gd->env_valid = ENV_VALID;
@@ -172,7 +172,7 @@
 			tmp_env2->crc;
 
 	if (!crc1_ok && !crc2_ok) {
-		set_default_env("bad CRC", 0);
+		env_set_default("bad CRC", 0);
 		return -ENOMSG; /* needed for env_load() */
 	} else if (crc1_ok && !crc2_ok) {
 		gd->env_valid = ENV_VALID;
@@ -236,10 +236,10 @@
 	if (gd->env_valid == ENV_INVALID) {
 #if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
 		/* Environment not changable */
-		set_default_env(NULL, 0);
+		env_set_default(NULL, 0);
 #else
 		bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
-		set_default_env("bad CRC", 0);
+		env_set_default("bad CRC", 0);
 #endif
 	} else {
 		env_load();