rework the way we reconsturct the object file order for syspatches

this change drops the exclude regex and just simply checks if the
object files are actually available and then constucts a response
file which we pass for linking and this seems to be good enough
to have reproducible make build output (which is what we want here)

ok tb@

share/mk/bsd.lib.mk

@@ -1,4 +1,4 @@
-#	$OpenBSD: bsd.lib.mk,v 1.105 2025/11/16 10:20:54 robert Exp $
+#	$OpenBSD: bsd.lib.mk,v 1.106 2026/03/17 17:07:58 robert Exp $
 #	$NetBSD: bsd.lib.mk,v 1.67 1996/01/17 20:39:26 mycroft Exp $
 #	@(#)bsd.lib.mk	5.26 (Berkeley) 5/2/91
 
@@ -206,22 +206,19 @@ lib${LIB}_p.a: ${POBJS}
 SOBJS+=	${OBJS:.o=.so}
 BUILDAFTER += ${SOBJS}
 
-# exclude from readelf(1) output for syspatch building
-EXCLUDE_REGEX:=	"(cmll-586|(comparetf|libgcc|unwind-dw)2|		\
-		mul(t|d|s|x)(c|f)3|crt(begin|end)S|			\
-		(div|umod|mod)(d|t)i3|emutls|(add|div|sub)tf3|		\
-		(fixtf|float|extend|trunctf)(d|s)(ftf2|i|itf|f2)|	\
-		outline_atomic_(ldadd|swp)(4|8)_4|aarch64|		\
-		floatunsitf|udivmodti4|AMDGPURegAsmNames|clear_cache)"
-
 ${FULLSHLIBNAME}: ${SOBJS} ${DPADD}
 	@echo building shared ${LIB} library \(version ${SHLIB_MAJOR}.${SHLIB_MINOR}\)
 	@rm -f ${.TARGET}
 .if defined(SYSPATCH_PATH)
+	@>${.TARGET}.rsp
+	@for _f in `readelf -Ws ${SYSPATCH_PATH}${LIBDIR}/${.TARGET} | \
+	    awk '/ FILE/{sub(".*/", "", $$NF); gsub(/\.[^.]+$$/, ".so", $$NF); \
+	    print $$NF}' | awk '!x[$$0]++'`; do \
+		[[ ! -f $${_f} ]] || echo $${_f} >>${.TARGET}.rsp; \
+	done
 	${CC} -shared -Wl,-soname,${FULLSHLIBNAME} ${PICFLAG} -o ${.TARGET} \
-	    `readelf -Ws ${SYSPATCH_PATH}${LIBDIR}/${.TARGET} | \
-	    awk '/ FILE/{sub(".*/", "", $$NF); gsub(/\..*/, ".so", $$NF); print $$NF}' | \
-	    egrep -v ${EXCLUDE_REGEX:C/[[:blank:]]//g} | awk '!x[$$0]++'` ${LDADD}
+	    @${.TARGET}.rsp ${LDADD}
+	@rm -f ${.TARGET}.rsp
 .else
 	${CC} -shared -Wl,-soname,${FULLSHLIBNAME} ${PICFLAG} -o ${.TARGET} \
 	    `echo ${SOBJS} | tr ' ' '\n' | sort -R` ${LDADD}