Fix misspelling of __clang_major__. * lib/cdefs.h (__THROW, __THROWNL, __NTH, __NTHNL): Fix misspelled macro name. * m4/gnulib-common.m4 (gl_COMMON_BODY): Likewise. * lib/malloc.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/stddef.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/stdio.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/stdlib.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/string.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/sys_stat.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise. * lib/wchar.in.h (_GL_ATTRIBUTE_NOTHROW): Likewise.