remove references to USER-OMP version of pair style nb3b/harmonic

doc/src/Commands_pair.txt

@@ -167,7 +167,7 @@ OPT.
 "morse/soft"_pair_morse.html,
 "multi/lucy"_pair_multi_lucy.html,
 "multi/lucy/rx (k)"_pair_multi_lucy_rx.html,
-"nb3b/harmonic (o)"_pair_nb3b_harmonic.html,
+"nb3b/harmonic"_pair_nb3b_harmonic.html,
 "nm/cut (o)"_pair_nm.html,
 "nm/cut/coul/cut (o)"_pair_nm.html,
 "nm/cut/coul/long (o)"_pair_nm.html,

doc/src/pair_nb3b_harmonic.txt

@@ -7,7 +7,6 @@
 :line
 
 pair_style nb3b/harmonic command :h3
-pair_style nb3b/harmonic/omp command :h3
 
 [Syntax:]
 
@@ -89,28 +88,6 @@ a particular simulation; LAMMPS ignores those entries.
 
 :line
 
-Styles with a {gpu}, {intel}, {kk}, {omp}, or {opt} suffix are
-functionally the same as the corresponding style without the suffix.
-They have been optimized to run faster, depending on your available
-hardware, as discussed on the "Speed packages"_Speed_packages.html doc
-page.  The accelerated styles take the same arguments and should
-produce the same results, except for round-off and precision issues.
-
-These accelerated styles are part of the GPU, USER-INTEL, KOKKOS,
-USER-OMP and OPT packages, respectively.  They are only enabled if
-LAMMPS was built with those packages.  See the "Build
-package"_Build_package.html doc page for more info.
-
-You can specify the accelerated styles explicitly in your input script
-by including their suffix, or you can use the "-suffix command-line
-switch"_Run_options.html when you invoke LAMMPS, or you can use the
-"suffix"_suffix.html command in your input script.
-
-See the "Speed packages"_Speed_packages.html doc page for more
-instructions on how to use the accelerated styles effectively.
-
-:line
-
 [Restrictions:]
 
 This pair style can only be used if LAMMPS was built with the MANYBODY