Fixes CI build script (#1350)

* Fix the parsing of /etc/os-release

The old code parses OS_DISTRO as 'PRETTY_Ubuntu' on Ubuntu and thus
never links to libtinfo correctly.

* Configurable CMAKE_PREFIX_PATH in CI script.

Author: xinyazhang

.ci/pytorch/build.sh

@@ -80,9 +80,7 @@ else
   elif [[ -v ANACONDA_PYTHON_VERSION ]]; then
     export CMAKE_PREFIX_PATH="/opt/conda/envs/py_${ANACONDA_PYTHON_VERSION}"
   else
-    # already checked by `! which conda`
-    CMAKE_PREFIX_PATH="$(conda info --base)"
-    export CMAKE_PREFIX_PATH
+    export CMAKE_PREFIX_PATH="$(conda info --base)"
   fi
 
   # Workaround required for MKL library linkage

cmake/Dependencies.cmake

@@ -1005,11 +1005,11 @@ if(USE_ROCM)
     set(DISTRO_VERSION "")
     foreach(line ${OS_RELEASE})
       string(REGEX MATCH "^NAME=" DISTRO_NAME_MATCH ${line})
-      if(NOT DISTRO_NAME_MATCH STREQUAL "")
+      if (NOT DISTRO_NAME_MATCH STREQUAL "")
         string(REGEX REPLACE "^NAME=\"(.*)\"" "\\1" DISTRO_NAME ${line})
       endif()
       string(REGEX MATCH "^VERSION_ID=" DISTRO_VERSION_MATCH ${line})
-      if(NOT DISTRO_VERSION_MATCH STREQUAL "")
+      if (NOT DISTRO_VERSION_MATCH STREQUAL "")
         string(REGEX REPLACE "^VERSION_ID=\"(.*)\"" "\\1" DISTRO_VERSION ${line})
       endif()
     endforeach()