[OpenImageIO/el6] Add cmake to BR.

[Richard Shaw]

commit 57952262a04877551102aa49372034798baf465e
Author: Richard M. Shaw <hobbes1069 at gmail.com>
Date:   Tue May 1 12:40:37 2012 -0500

    Add cmake to BR.

 OpenImageIO.spec |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/OpenImageIO.spec b/OpenImageIO.spec
index 36c33d8..a853c6b 100644
--- a/OpenImageIO.spec
+++ b/OpenImageIO.spec
@@ -17,6 +17,7 @@ Patch0:         OpenImageIO-1.0.0-use_external_tbb.patch
 Patch1:         OpenImageIO-1.0.0-tbb_include.patch
 Patch2:         OpenImageIO-1.0.3-ppc64.patch
 
+BuildRequires:  cmake
 BuildRequires:  boost-devel glew-devel qt-devel OpenEXR-devel ilmbase-devel
 BuildRequires:  python2-devel txt2man
 BuildRequires:  libpng-devel libtiff-devel openjpeg-devel
@@ -76,8 +77,7 @@ install -pm 0644 %{SOURCE1} src/cmake/modules/
 
 
 %build
-mkdir -p build
-pushd build
+rm -rf build && mkdir -p build && pushd build
 # CMAKE_SKIP_RPATH is OK here because it is set to FALSE internally and causes
 # CMAKE_INSTALL_RPATH to be cleared, which is the desiered result.
 %cmake -DCMAKE_BUILD_TYPE=RelWithDebInfo \