COMP: Remove unused netlib linalg lsmr solver

The lsmrBase/lsmrDense least-squares solver in the vendored netlib
linalg/ directory has no vnl_* wrapper (unlike lsqr, which vnl_lsqr
exposes) and no consumer anywhere in ITK or the downstream forest
(ANTs, BRAINSTools, Slicer). Only its own self-test referenced it, so
the sources are compiled-but-dead weight in itkv3p_netlib. Drop the
four sources and the netlib_lsmrTest2 self-test.

Author: hjmjohnson

Modules/ThirdParty/VNL/src/vxl/v3p/netlib/CMakeLists.txt

@@ -130,8 +130,6 @@ set(V3P_NETLIB_opt_SOURCES
 set(V3P_NETLIB_linalg_SOURCES
      linalg/lsqrBase.cxx linalg/lsqrBase.h
      linalg/lsqrDense.cxx linalg/lsqrDense.h
-     linalg/lsmrBase.cxx linalg/lsmrBase.h
-     linalg/lsmrDense.cxx linalg/lsmrDense.h
    )
 set(V3P_NETLIB_sparse_SOURCES
      sparse/spAllocate.c
@@ -192,7 +190,7 @@ vxl_add_library(
 )
 
 target_link_libraries(itkv3p_netlib PRIVATE ${VXL_PLATFORM_MATH_LIBRARIES})
-# The linalg/ subdirectory holds the lsqr/lsmr C++ headers that consumers
+# The linalg/ subdirectory holds the lsqr C++ headers that consumers
 # (e.g. vnl_lsqr) include directly; expose it so they need no manual path.
 target_include_directories(itkv3p_netlib PUBLIC
     "$<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/linalg>")