INSTALL: clarify 386 and no-sse2 options.

Reviewed-by: Rich Salz <rsalz@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>

Configure

diff --git a/Configure b/Configure
index 2bdf87b..c005781 100755
--- a/Configure
+++ b/Configure
@@ -60,11 +60,12 @@
 # zlib-dynamic	Like "zlib", but the zlib library is expected to be a shared
 #		library and will be loaded in run-time by the OpenSSL library.
 # sctp          include SCTP support
-# 386           generate 80386 code
 # enable-weak-ssl-ciphers
 #               Enable weak ciphers that are disabled by default. This currently
 #               only includes RC4 based ciphers.
-# no-sse2	disables IA-32 SSE2 code, above option implies no-sse2
+# 386           generate 80386 code in assembly modules
+# no-sse2       disables IA-32 SSE2 code in assembly modules, the above
+#               mentioned '386' option implies this one
 # no-<cipher>   build without specified algorithm (rsa, idea, rc5, ...)
 # -<xxx> +<xxx> compiler options are passed through
 # -static       while -static is also a pass-through compiler option (and