Fix Faz-Hernández ref

For some reason, bibtex parses Faz-Hern\'andez as to be references
with FH, instead of just F (perhaps because of the 'and' suffix?).
This commit updates the definitions of Faz-Hernández' name to
"Faz-Hern\'andez".

Because we were not using \bibliographystyle{alpha}, this should
have no visual consequences.

refs.bib

@@ -247,7 +247,7 @@
 }
 
 @inproceedings{OLH+18,
-  author        = {Thomaz Oliveira and Julio López and H\"useyin H{\i}\c{s}{\i}l and Armando Faz-Hern\'andez and Francisco Rodr\'iguez-Henr\'iquez},
+  author        = {Thomaz Oliveira and Julio López and H\"useyin H{\i}\c{s}{\i}l and Armando {Faz-Hern\'andez} and Francisco Rodr\'iguez-Henr\'iquez},
   title         = {How to ({Pre}-){Compute} a {Ladder}},
   booktitle     = {Selected {Areas} in {Cryptography} -- {SAC} 2017},
   editor        = {Carlisle Adams and Jan Camenisch},
@@ -314,7 +314,7 @@
 }
 
 @inproceedings{FL15,
-  author        = {Armando Faz-Hern\'andez and Julio L\'opez},
+  author        = {Armando {Faz-Hern\'andez} and Julio L\'opez},
   title         = {Fast Implementation of {Curve25519} Using {AVX2}},
   booktitle     = {Progress in {Cryptology} -- {LATINCRYPT} 2015},
   editor        = {Kristin Lauter and Francisco Rodr\'iguez-Henr\'iquez},