Remove version.c from .gitignore

This commit removes version.c from .gitignore as version 4.0 will not
include version generation.

Signed-off-by: Harry Ramsey <harry.ramsey@arm.com>
diff --git a/tf-psa-crypto/drivers/builtin/src/.gitignore b/tf-psa-crypto/drivers/builtin/src/.gitignore
index f3923b1..9e36d25 100644
--- a/tf-psa-crypto/drivers/builtin/src/.gitignore
+++ b/tf-psa-crypto/drivers/builtin/src/.gitignore
@@ -1,4 +1,3 @@
 ###START_GENERATED_FILES###
 /error.c
-/version_features.c
 ###END_GENERATED_FILES###