Fix MSVC warning in DetectRecursion.cpp.
Fix MSVC warning in DetectRecursion.cpp.

In preparation for turning on warnings as errors.
Review URL: https://codereview.appspot.com/5564053

git-svn-id: 947ae547afacb859f3991e003b9d6feb04be57d7@959 736b8ea6-26fd-11df-bfd4-992fa37f6226

spurious/angle-mirror,adobe/angle.js,MIPS/external-chromium_org-third_party-angle,Mustaavalkosta/android_external_angle,jgcaaprom/android_external_chromium_org_third_party_angle,xin3liang/platform_external_chromium_org_third_party_angle,xin3liang/platform_external_chromium_org_third_party_angle,Mustaavalkosta/android_external_angle,android-ia/platform_external_chromium_org_third_party_angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,dumganhar/angleproject,jgcaaprom/android_external_chromium_org_third_party_angle,MIPS/external-chromium_org-third_party-angle,adobe/angle.js,xin3liang/platform_external_chromium_org_third_party_angle,MIPS/external-chromium_org-third_party-angle,dumganhar/angleproject,jgcaaprom/android_external_chromium_org_third_party_angle,Mustaavalkosta/android_external_angle,adobe/angle.js,MIPS/external-chromium_org-third_party-angle,jgcaaprom/android_external_chromium_org_third_party_angle,spurious/angle-mirror,Mustaavalkosta/android_external_angle,xin3liang/platform_external_chromium_org_third_party_angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,adobe/angle.js,geekboxzone/lollipop_external_chromium_org_third_party_angle,android-ia/platform_external_chromium_org_third_party_angle,geekboxzone/lollipop_external_chromium_org_third_party_angle,android-ia/platform_external_chromium_org_third_party_angle,dumganhar/angleproject,android-ia/platform_external_chromium_org_third_party_angle,dumganhar/angleproject,spurious/angle-mirror,spurious/angle-mirror