make 3.82 bug with leading space on member names in library prerequisite.

[Duncan Moore]

Using this makefile:
.PHONY: all
all: lib.a( a.o)
(%.o): %.o
    @echo $@ $<

make 3.81 gives what I would expect:
lib.a a.o

make 3.82, with the corrections for bug #30612, gives:
make: *** No rule to make target `lib.a()', needed by `all'.  Stop.