[clang] [flang] [Flang][Driver] Enable the -B option (PR #109965)

[Kiran Chandramohan via cfe-commits]

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@@ -0,0 +1,23 @@
+! Check -B driver option.
+!
+! Target triple prefix is not detected for -B.
+! RUN: %flang %s -### -o %t.o -target i386-unknown-linux \
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kiranchandramohan wrote:

Thanks. Done. Modified tests for both drivers.

https://github.com/llvm/llvm-project/pull/109965