fix alignment for new-style ctors when using riscv64

Recently uClibc-ng enabled UCLIBC_CTOR_DTOR for riscv64, so
that f.e. C++ applications are running fine. As a side effect
this breaks noMMU support. The problem is the alignment for
the ctors in elf2flt. This patch fixes it.

Tested with Qemu for ARM, M68k and Xtensa with no regressions.

elf2flt.ld.in

@@ -139,7 +139,7 @@ R_RODAT:	*(.gnu.linkonce.r*)
 		@SYMBOL_PREFIX@_ssro_size = @SYMBOL_PREFIX@_essro - @SYMBOL_PREFIX@_ssro;
 		PROVIDE(@SYMBOL_PREFIX@_SDA2_BASE_ = @SYMBOL_PREFIX@_ssro + (@SYMBOL_PREFIX@_ssro_size / 2));
 
-		. = ALIGN(4) ;
+		. = ALIGN(8) ;
 TOR:		@SYMBOL_PREFIX@__CTOR_LIST__ = .;
 TOR:		LONG((@SYMBOL_PREFIX@__CTOR_END__ - @SYMBOL_PREFIX@__CTOR_LIST__) / 4 - 2)
 SINGLE_LINK:	/* gcc uses crtbegin.o to find the start of