Move opensslconf.h to a machine-independent place

After drilling through many layers of fossilized turds from a
long-forgotten millenium, jsing and I finally found oil^Wa
machine-independent version of opensslconf.h.

Remove the no longer needed versions in arch/*/ and move one copy
to the top level.  Add an RCS tag and place the remaining garbage
in the public domain.

ok jsing

Author: tb

src/lib/libcrypto/Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.242 2025/08/14 15:48:48 beck Exp $
+# $OpenBSD: Makefile,v 1.243 2025/08/25 16:48:01 tb Exp $
 
 LIB=	crypto
 LIBREBUILD=y
@@ -674,6 +674,7 @@ HDRS=\
 	${LCRYPTO_SRC}/modes/modes.h \
 	${LCRYPTO_SRC}/objects/objects.h \
 	${LCRYPTO_SRC}/ocsp/ocsp.h \
+	${LCRYPTO_SRC}/opensslconf.h \
 	${LCRYPTO_SRC}/opensslfeatures.h \
 	${LCRYPTO_SRC}/opensslv.h \
 	${LCRYPTO_SRC}/ossl_typ.h \
@@ -699,7 +700,6 @@ HDRS=\
 	${LCRYPTO_SRC}/x509/x509v3.h
 
 HDRS_GEN=\
-	${.CURDIR}/arch/${MACHINE_CPU}/opensslconf.h \
 	${.OBJDIR}/obj_mac.h
 
 prereq: obj_mac.h