meta: enable parallel build for several recipes

I used a for loop to build these packages more than 520 times, these
recipes never failed.

(From OE-Core rev: 7957c5bc2771a763d26e50e716733c6335cef3c2)

Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

meta/recipes-support/icu/icu.inc

@@ -10,7 +10,6 @@ S = "${WORKDIR}/icu/source"
 SPDX_S = "${WORKDIR}/icu"
 STAGING_ICU_DIR_NATIVE = "${STAGING_DATADIR_NATIVE}/${BPN}/${PV}"
 
-PARALLEL_MAKE = ""
 CPPFLAGS_append_libc-uclibc = " -DU_TIMEZONE=0"
 
 BINCONFIG = "${bindir}/icu-config"

meta/recipes-support/libpcre/libpcre_8.36.bb

@@ -28,8 +28,6 @@ BINCONFIG = "${bindir}/pcre-config"
 
 inherit autotools binconfig-disabled ptest
 
-PARALLEL_MAKE = ""
-
 EXTRA_OECONF = "\
     --enable-newline-is-lf \
     --enable-rebuild-chartables \