Unify Assembler files between Linux and Windows

Add new macro ASMABI used by Windows to change
calling API to "sysv_abi".

Reviewed-by: Attila Fülöp <attila@fueloep.org>
Reviewed-by: Richard Yao <richard.yao@alumni.stonybrook.edu>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jorgen Lundman <lundman@lundman.net>
Closes #14228

include/os/freebsd/Makefile.am

@@ -6,6 +6,8 @@ noinst_HEADERS = \
 	\
 	%D%/spl/rpc/xdr.h \
 	\
+	%D%/spl/sys/ia32/asm_linkage.h \
+	\
 	%D%/spl/sys/acl.h \
 	%D%/spl/sys/acl_impl.h \
 	%D%/spl/sys/atomic.h \
@@ -88,3 +90,4 @@ noinst_HEADERS = \
 	%D%/zfs/sys/zfs_vnops_os.h \
 	%D%/zfs/sys/zfs_znode_impl.h \
 	%D%/zfs/sys/zpl.h
+