lib/msun: centralize addition of the arch-specific symbol map files

This also adds the aarch64 symbols, exporting them.

Reported and tested by:	fluffy
Reviewed by:	emaste
Fixes:	3a01e1e1a5
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
Differential revision:	https://reviews.freebsd.org/D56283

lib/msun/Makefile

@@ -115,6 +115,7 @@ LIBC_ARCH=${MACHINE_CPUARCH}
 CFLAGS+=	-I${.CURDIR}/src -I${LIBC_SRCTOP}/include \
 		-I${LIBC_SRCTOP}/${LIBC_ARCH}
 SYM_MAPS+=	${.CURDIR}/Symbol.map
+SYM_MAPS+=	${.CURDIR}/${ARCH_SUBDIR}/Symbol.map
 
 VERSION_DEF=	${LIBC_SRCTOP}/Versions.def
 SYMBOL_MAPS=	${SYM_MAPS}

lib/msun/amd64/Makefile.inc

@@ -6,4 +6,3 @@ ARCH_SRCS = e_fmod.S e_fmodf.S e_fmodl.S \
 	    s_remquo.S s_remquof.S s_remquol.S \
 	    s_rintl.S s_scalbn.S s_scalbnf.S s_scalbnl.S
 LDBL_PREC = 64
-SYM_MAPS += ${.CURDIR}/amd64/Symbol.map

lib/msun/arm/Makefile.inc

@@ -1,5 +1,4 @@
 LDBL_PREC = 53
-SYM_MAPS += ${.CURDIR}/arm/Symbol.map
 
 .if defined(CPUTYPE) && ${CPUTYPE:M*soft*} != ""
 ARCH_SRCS = fenv-softfp.c fenv-vfp.c

lib/msun/i387/Makefile.inc

@@ -17,4 +17,3 @@ ARCH_SRCS+= e_fmodl.S \
 	    s_logbl.S s_lrintl.S s_remquol.S s_rintl.S s_scalbnl.S s_truncl.S
 
 LDBL_PREC = 64	# XXX 64-bit format, but truncated to 53 bits
-SYM_MAPS += ${.CURDIR}/i387/Symbol.map

lib/msun/powerpc/Makefile.inc

@@ -1,2 +1 @@
 LDBL_PREC = 53
-SYM_MAPS += ${.CURDIR}/powerpc/Symbol.map

lib/msun/riscv/Makefile.inc

@@ -1,2 +1 @@
 LDBL_PREC = 113
-SYM_MAPS += ${.CURDIR}/riscv/Symbol.map