Update SONAME_VERSION in SConscript

Change-Id: I8e5695dc7f9e9dd4b3b81487b1ad991920a12292
Signed-off-by: Sang-Hoon Park <sang-hoon.park@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/3768
Reviewed-by: Pablo Marquez <pablo.tello@arm.com>
Reviewed-by: SiCong Li <sicong.li@arm.com>
Tested-by: Gian Marco Iodice <gianmarco.iodice@arm.com>
diff --git a/SConscript b/SConscript
index 2bbbc22..49f2976 100644
--- a/SConscript
+++ b/SConscript
@@ -25,8 +25,8 @@
 import subprocess
 
 VERSION = "v0.0-unreleased"
-LIBRARY_VERSION_MAJOR = 18
-LIBRARY_VERSION_MINOR =  1
+LIBRARY_VERSION_MAJOR = 20
+LIBRARY_VERSION_MINOR =  0
 LIBRARY_VERSION_PATCH =  0
 SONAME_VERSION = str(LIBRARY_VERSION_MAJOR) + "." + str(LIBRARY_VERSION_MINOR) + "." + str(LIBRARY_VERSION_PATCH)