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.

(cherry picked from commit 090d95f)

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

@@ -1025,6 +1025,31 @@ endif()
 
 # ---[ HIP
 if(USE_ROCM)
+  # This prevents linking in the libtinfo from /opt/conda/lib which conflicts with ROCm libtinfo.
+  # Currently only active for Ubuntu 20.04 and greater versions.
+  if(UNIX AND EXISTS "/etc/os-release")
+    file(STRINGS /etc/os-release OS_RELEASE)
+    set(DISTRO_NAME "")
+    set(DISTRO_VERSION "")
+    foreach(line ${OS_RELEASE})
+      string(REGEX MATCH "^NAME=" DISTRO_NAME_MATCH ${line})
+      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 "")
+        string(REGEX REPLACE "^VERSION_ID=\"(.*)\"" "\\1" DISTRO_VERSION ${line})
+      endif()
+    endforeach()
+    if(DISTRO_NAME STREQUAL "Ubuntu" AND DISTRO_VERSION VERSION_GREATER_EQUAL "20.04")
+      find_library(LIBTINFO_LOC tinfo NO_CMAKE_PATH NO_CMAKE_ENVIRONMENT_PATH)
+      if(LIBTINFO_LOC)
+        get_filename_component(LIBTINFO_LOC_PARENT ${LIBTINFO_LOC} DIRECTORY)
+        set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -Wl,-rpath-link,${LIBTINFO_LOC_PARENT}")
+      endif()
+    endif()
+  endif()
+
   include(${CMAKE_CURRENT_LIST_DIR}/public/LoadHIP.cmake)
   if(PYTORCH_FOUND_HIP)
     message(INFO "Compiling with HIP for AMD.")