release: Zephyr v4.0.0

Set the version to v4.0.0

Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>

VERSION

diff --git a/VERSION b/VERSION
index 78abb38..be5e518 100644
--- a/VERSION
+++ b/VERSION
@@ -2,4 +2,4 @@
 VERSION_MINOR = 0
 PATCHLEVEL = 0
 VERSION_TWEAK = 0
-EXTRAVERSION = rc3
+EXTRAVERSION =