package/cryptopp: purge trailing '/' from CRYPTOPP_SITE

<PKG>_SITE cannot have a trailing slash.

This was not detected by the check in generic-package because it is a
host-only package without Config.in symbol.

Signed-off-by: Carlos Santos <casantos@datacom.com.br>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>

package/cryptopp/cryptopp.mk

@@ -6,7 +6,7 @@
 
 CRYPTOPP_VERSION = 7.0.0
 CRYPTOPP_SOURCE = cryptopp$(subst .,,$(CRYPTOPP_VERSION)).zip
-CRYPTOPP_SITE = http://cryptopp.com/
+CRYPTOPP_SITE = http://cryptopp.com
 CRYPTOPP_LICENSE = BSL-1.0
 CRYPTOPP_LICENSE_FILES = License.txt
 CRYPTOPP_INSTALL_STAGING = YES