[GHC] #10223: Cleanup `mk/build.mk.sample`

[GHC]

#10223: Cleanup `mk/build.mk.sample`
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        Reporter:  thomie            |                   Owner:  thomie
            Type:  task              |                  Status:  new
        Priority:  normal            |               Milestone:  7.12.1
       Component:  Compiler          |                 Version:  7.10.1
      Resolution:                    |                Keywords:
Operating System:  Unknown/Multiple  |            Architecture:
                                     |  Unknown/Multiple
 Type of failure:  None/Unknown      |               Test Case:
      Blocked By:                    |                Blocking:
 Related Tickets:                    |  Differential Revisions:
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Comment (by Thomas Miedema <thomasmiedema@…>):

 In [changeset:"330fbbdacc71a7bb465195e24e268a947fe97412/ghc"
 330fbbda/ghc]:
 {{{
 #!CommitTicketReference repository="ghc"
 revision="330fbbdacc71a7bb465195e24e268a947fe97412"
 Build system: make *-cross BuildFlavours consistent (#10223)

 This is a follow up to 841924c9587c10488a18e307b573720977bf4f13,
 where `-fllvm` was explicitly removed from GhcStage1HcOpts for
 perf-cross.

 After removing -fllvm from GhcStage1HcOpts, it should be removed from
 SRC_HC_OPTS as well, because SRC_HC_OPTS are added to every Haskell
 compilation. That's what this patch does.

 BuildFlavour bench-cross (added in
 ddf79ebf69fe4a6e69d69d451a6040a53b1ea12c),
 is probably never used. But for consistency, also use -fllvm here, for
 building stage2 and the libraries.

 Reviewed by: austin

 Differential Revision: https://phabricator.haskell.org/D1228
 }}}

--
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/10223#comment:10>
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