mesa: turn off 'x' bit misset on a few .h and .syn files

diff --git a/src/mesa/shader/slang/library/slang_pp_directives.syn b/src/mesa/shader/slang/library/slang_pp_directives.syn
old mode 100755 (executable)
new mode 100644 (file)

diff --git a/src/mesa/shader/slang/library/slang_pp_expression.syn b/src/mesa/shader/slang/library/slang_pp_expression.syn
old mode 100755 (executable)
new mode 100644 (file)

diff --git a/src/mesa/shader/slang/library/slang_version.syn b/src/mesa/shader/slang/library/slang_version.syn
old mode 100755 (executable)
new mode 100644 (file)

diff --git a/src/mesa/shader/slang/library/slang_version_syn.h b/src/mesa/shader/slang/library/slang_version_syn.h
old mode 100755 (executable)
new mode 100644 (file)