toolchain-external: CodeSourcery MIPS update upstream URL

The current URL returns error 403: Forbidden, so switch to https.

Signed-off-by: Romain Naour <romain.naour@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
(cherry picked from commit 25902b111a93e562e3c1991f65c03649c88802c4)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

toolchain/toolchain-external/toolchain-external-codesourcery-mips/toolchain-external-codesourcery-mips.mk

@@ -6,7 +6,7 @@
 
 TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_VERSION = 2016.05-8
 
-TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_SITE = http://sourcery.mentor.com/public/gnu_toolchain/$(TOOLCHAIN_EXTERNAL_PREFIX)
+TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_SITE = https://sourcery.mentor.com/public/gnu_toolchain/$(TOOLCHAIN_EXTERNAL_PREFIX)
 TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_SOURCE = mips-$(TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_VERSION)-$(TOOLCHAIN_EXTERNAL_PREFIX)-i686-pc-linux-gnu.tar.bz2
 TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_ACTUAL_SOURCE_TARBALL = mips-$(TOOLCHAIN_EXTERNAL_CODESOURCERY_MIPS_VERSION)-$(TOOLCHAIN_EXTERNAL_PREFIX).src.tar.bz2