release: Zephyr 3.2.0-rc3

Set version to v3.2.0-rc3.

Signed-off-by: Fabio Baltieri <fabiobaltieri@google.com>
Signed-off-by: Mahesh Mahadevan <mahesh.mahadevan@nxp.com>
diff --git a/VERSION b/VERSION
index 1cba161..f37fa8a 100644
--- a/VERSION
+++ b/VERSION
@@ -2,4 +2,4 @@
 VERSION_MINOR = 2
 PATCHLEVEL = 0
 VERSION_TWEAK = 0
-EXTRAVERSION = rc2
+EXTRAVERSION = rc3