8278163: --with-cacerts-src variable resolved after GenerateCacerts recipe setup

Reviewed-by: sgehwolf
Backport-of: 45da3aea22fd85f214e661b2c98631cb91ddb55d

Author: Andrew Leonard

make/modules/java.base/Gendata.gmk

@@ -60,7 +60,11 @@ TARGETS += $(GENDATA_CURDATA)
 
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-GENDATA_CACERTS_SRC := $(TOPDIR)/make/data/cacerts/
+ifneq ($(CACERTS_SRC), )
+  GENDATA_CACERTS_SRC := $(CACERTS_SRC)
+else
+  GENDATA_CACERTS_SRC := $(TOPDIR)/make/data/cacerts/
+endif
 GENDATA_CACERTS := $(SUPPORT_OUTPUTDIR)/modules_libs/java.base/security/cacerts
 
 $(GENDATA_CACERTS): $(BUILD_TOOLS_JDK) $(wildcard $(GENDATA_CACERTS_SRC)/*)
@@ -71,9 +75,6 @@ $(GENDATA_CACERTS): $(BUILD_TOOLS_JDK) $(wildcard $(GENDATA_CACERTS_SRC)/*)
 ifeq ($(CACERTS_FILE), )
   TARGETS += $(GENDATA_CACERTS)
 endif
-ifneq ($(CACERTS_SRC), )
-  GENDATA_CACERTS_SRC := $(CACERTS_SRC)
-endif
 
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