release: Zephyr 4.3.0-rc2

Update the version to v4.3.0-rc2.

Signed-off-by: Johan Hedberg <[email protected]>
Signed-off-by: Chris Friedt <[email protected]>

Author: Chris Friedt

VERSION

@@ -2,4 +2,4 @@ VERSION_MAJOR = 4
 VERSION_MINOR = 3
 PATCHLEVEL = 0
 VERSION_TWEAK = 0
-EXTRAVERSION = rc1
+EXTRAVERSION = rc2