[gcc r12-6983] [COMMITTED] Change multiprecision.org to use https

[gcc r12-6983] [COMMITTED] Change multiprecision.org to use https

[Andrew Pinski]

https://gcc.gnu.org/g:6bc732eba9a7dcf2e948c27814b37d30e0a47542

commit r12-6983-g6bc732eba9a7dcf2e948c27814b37d30e0a47542
Author: Andrew Pinski <apinski@marvell.com>
Date:   Tue Feb 1 23:05:14 2022 +0000

    [COMMITTED] Change multiprecision.org to use https
    
    As reported at
    https://gcc.gnu.org/pipermail/gcc/2022-February/238216.html,
    multiprecision.org now uses https so this updates the documentation
    to use https instead of http.
    
    Committed as obvious.
    
    gcc/ChangeLog:
    
            * doc/install.texi:

Diff:
---
 gcc/doc/install.texi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index f4e7dc42198..deb99388e5b 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -406,7 +406,7 @@ download_prerequisites installs.
 @item MPC Library version 1.0.1 (or later)
 
 Necessary to build GCC@.  It can be downloaded from
-@uref{http://www.multiprecision.org/mpc/}.  If an MPC source distribution
+@uref{https://www.multiprecision.org/mpc/}.  If an MPC source distribution
 is found in a subdirectory of your GCC sources named @file{mpc}, it
 will be built together with GCC.  Alternatively, if MPC is already
 installed but it is not in your default library search path, the