tests: rename routers in nhrp_redundancy

tests: rename routers in nhrp_redundancy

Rename routers in nhrp_redundancy to match the diagram. Cosmetic change.

> cd tests/topotests/nhrp_redundancy
> git grep r1  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r1|nhs1|g' -i
> git grep r2  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r2|nhs2|g' -i
> git grep r3  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r3|nhs3|g' -i
> git grep r4  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r4|nhc1|g' -i
> git grep r5  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r5|nhc2|g' -i
> git grep r6  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r6|router|g' -i
> git grep r7  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|r7|host|g' -i
>
> git grep R1  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R1|nhs1|g' -i
> git grep R2  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R2|nhs2|g' -i
> git grep R3  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R3|nhs3|g' -i
> git grep R4  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R4|nhc1|g' -i
> git grep R5  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R5|nhc2|g' -i
> git grep R6  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R6|router|g' -i
> git grep R7  | cut -f1 -d: | uniq | xargs -L1 sed -e 's|R7|host|g' -i
>
> mv r1 nhs1
> mv r2 nhs2
> mv r3 nhs3
> mv r4 nhc1
> mv r5 nhc2
> mv r6 router
> mv r7 host

Signed-off-by: Louis Scalbert <louis.scalbert@6wind.com>
(cherry picked from commit 3f49c5026c3f6ebc1583951f145b77d479abb834)