Address the clang 13 "changed binding to STB_WEAK" warning on arm (32bit):

Address the clang 13 "changed binding to STB_WEAK" warning on arm (32bit):
 * add _?ENTRY_NB to arm/asm.h
 * make sure ld.so's arm asm bits see the same includes as libc
 * switch libc's arm bits to the generic DEFS.h
 * switch arm ASM bits from ENTRY to ENTRY_NB as necessary

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