[PATCH] fix x86 initrd breakage

Summary: 2.5.17 broke initrd on x86. Fix below.

Why: Kai's patch in 2.5.17 to move x86-specific options from
Makefile to arch/i386/boot/Makefile unfortunately lost the fact
that the orginal "#export RAMDISK = -DRAMDISK=512" statement
was commented out. (I suspect a typo.) RAMDISK is obsolete since
1.3.something, and uncommenting it has "interesting" effects
since the ram_size field has a very different meaning now.

The patch below reverts the statement to its pre-2.5.17 state.
Perhaps it should be removed altogether?

arch/i386/boot/Makefile

@@ -23,7 +23,7 @@ SVGA_MODE := -DSVGA_MODE=NORMAL_VGA
 
 # If you want the RAM disk device, define this to be the size in blocks.
 
-RAMDISK := -DRAMDISK=512
+#RAMDISK := -DRAMDISK=512
 
 # ---------------------------------------------------------------------------