openssl.inc: Use cp -L, busybox cp doesn't support the long option.

openssl.inc: Use cp -L, busybox cp doesn't support the long option.

Reported by andyzammy on IRC.

| oe_libinstall: cd /home/rofl/Desktop/oe/angstrom-setup-scripts/build/tmp-angstrom_2008_1/work/i686-linux/openssl-native-1.0.0b-r13.1/openssl-1.0.0b
| cp: unrecognized option '--dereference'
| BusyBox v1.13.3 (Ubuntu 1:1.13.3-1ubuntu11) multi-call binary
|
| Usage: cp [OPTION]... SOURCE DEST
|
| Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY
|
| Options:
| 	-a	Same as -dpR
| 	-d,-P	Preserve links
| 	-H,-L	Dereference all symlinks (default)
| 	-p	Preserve file attributes if possible
| 	-f	Force overwrite
| 	-i	Prompt before overwrite
| 	-R,-r	Recurse directories
| 	-l,-s	Create (sym)links
|
| ERROR: Function do_install failed

Signed-off-by: Graham Gower <graham.gower@gmail.com>
Acked-by: Khem Raj <raj.khem@gmail.com>