kbuild: enable arch/s390/include/uapi/asm/zcrypt.h for uapi header test

Masahiro Yamada changed the zcrypt.h header file to use __u{16,32,64}
instead of uint{16,32,64}_t with ("s390: use __u{16,32,64} instead of
uint{16,32,64}_t in uapi header").

This makes all s390 header files pass - remove zcrypt.h from the blacklist.

Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
diff --git a/usr/include/Makefile b/usr/include/Makefile
index aa316d9..1fb6abe 100644
--- a/usr/include/Makefile
+++ b/usr/include/Makefile
@@ -101,10 +101,6 @@
 header-test- += linux/bpf_perf_event.h
 endif
 
-ifeq ($(SRCARCH),s390)
-header-test- += asm/zcrypt.h
-endif
-
 ifeq ($(SRCARCH),sparc)
 header-test- += asm/stat.h
 header-test- += asm/uctx.h